Update grammar syntax comment for conditional updates
Update grammar syntax comment for conditional updates

Patch by Brian O'Neill; reviewed by Tyler Hobbs for CASSANDRA-8908

sharvanath/cassandra,snazy/cassandra,ifesdjeen/cassandra,pallavi510/cassandra,iamaleksey/cassandra,cooldoger/cassandra,likaiwalkman/cassandra,juiceblender/cassandra,bpupadhyaya/cassandra,snazy/cassandra,yangzhe1991/cassandra,mambocab/cassandra,aarushi12002/cassandra,dkua/cassandra,chaordic/cassandra,tongjixianing/projects,aweisberg/cassandra,mkjellman/cassandra,pallavi510/cassandra,jeromatron/cassandra,knifewine/cassandra,boneill42/cassandra,kgreav/cassandra,pcmanus/cassandra,christian-esken/cassandra,guard163/cassandra,tjake/cassandra,christian-esken/cassandra,darach/cassandra,carlyeks/cassandra,fengshao0907/Cassandra-Research,pkdevbox/cassandra,helena/cassandra,Imran-C/cassandra,DICL/cassandra,WorksApplications/cassandra,pofallon/cassandra,beobal/cassandra,kgreav/cassandra,swps/cassandra,tommystendahl/cassandra,yukim/cassandra,xiongzheng/Cassandra-Research,tommystendahl/cassandra,adelapena/cassandra,thobbs/cassandra,belliottsmith/cassandra,AtwooTM/cassandra,iburmistrov/Cassandra,spodkowinski/cassandra,jasonstack/cassandra,exoscale/cassandra,ptnapoleon/cassandra,pcmanus/cassandra,bdeggleston/cassandra,mashuai/Cassandra-Research,jasonwee/cassandra,pofallon/cassandra,mambocab/cassandra,jeffjirsa/cassandra,yukim/cassandra,Jaumo/cassandra,a-buck/cassandra,weipinghe/cassandra,josh-mckenzie/cassandra,rmarchei/cassandra,blambov/cassandra,fengshao0907/Cassandra-Research,jeffjirsa/cassandra,asias/cassandra,cooldoger/cassandra,pauloricardomg/cassandra,sedulam/CASSANDRA-12201,phact/cassandra,DikangGu/cassandra,adejanovski/cassandra,christian-esken/cassandra,kangkot/stratio-cassandra,stef1927/cassandra,michaelsembwever/cassandra,sayanh/ViewMaintenanceSupport,ben-manes/cassandra,Jaumo/cassandra,jbellis/cassandra,aweisberg/cassandra,dongjiaqiang/cassandra,likaiwalkman/cassandra,pauloricardomg/cassandra,jrwest/cassandra,thobbs/cassandra,pauloricardomg/cassandra,asias/cassandra,mshuler/cassandra,fengshao0907/Cassandra-Research,dongjiaqiang/cassandra,emolsson/cassandra,dongjiaqiang/cassandra,sluk3r/cassandra,instaclustr/cassandra,rmarchei/cassandra,rmarchei/cassandra,yangzhe1991/cassandra,whitepages/cassandra,blambov/cassandra,blambov/cassandra,jeromatron/cassandra,clohfink/cassandra,nutbunnies/cassandra,pofallon/cassandra,spodkowinski/cassandra,regispl/cassandra,adelapena/cassandra,caidongyun/cassandra,adelapena/cassandra,snazy/cassandra,yukim/cassandra,tjake/cassandra,szhou1234/cassandra,michaelsembwever/cassandra,apache/cassandra,MasahikoSawada/cassandra,JeremiahDJordan/cassandra,jasonwee/cassandra,Stratio/stratio-cassandra,jasobrown/cassandra,bcoverston/cassandra,RyanMagnusson/cassandra,beobal/cassandra,codefollower/Cassandra-Research,newrelic-forks/cassandra,joesiewert/cassandra,weideng1/cassandra,joesiewert/cassandra,pauloricardomg/cassandra,ejankan/cassandra,josh-mckenzie/cassandra,sedulam/CASSANDRA-12201,aureagle/cassandra,bmel/cassandra,Jaumo/cassandra,ollie314/cassandra,WorksApplications/cassandra,clohfink/cassandra,pthomaid/cassandra,krummas/cassandra,kangkot/stratio-cassandra,blerer/cassandra,stef1927/cassandra,WorksApplications/cassandra,MasahikoSawada/cassandra,joesiewert/cassandra,scylladb/scylla-tools-java,cooldoger/cassandra,JeremiahDJordan/cassandra,kgreav/cassandra,strapdata/cassandra,bcoverston/cassandra,sivikt/cassandra,juiceblender/cassandra,tongjixianing/projects,jbellis/cassandra,helena/cassandra,WorksApplications/cassandra,Stratio/stratio-cassandra,swps/cassandra,belliottsmith/cassandra,yhnishi/cassandra,michaelmior/cassandra,chaordic/cassandra,bpupadhyaya/cassandra,adejanovski/cassandra,Instagram/cassandra,bcoverston/cassandra,exoscale/cassandra,driftx/cassandra,pallavi510/cassandra,instaclustr/cassandra,weipinghe/cassandra,jrwest/cassandra,chaordic/cassandra,iburmistrov/Cassandra,belliottsmith/cassandra,weideng1/cassandra,mambocab/cassandra,spodkowinski/cassandra,krummas/cassandra,rogerchina/cassandra,pcn/cassandra-1,mashuai/Cassandra-Research,ifesdjeen/cassandra,rogerchina/cassandra,jasobrown/cassandra,mike-tr-adamson/cassandra,instaclustr/cassandra,pcn/cassandra-1,gdusbabek/cassandra,yhnishi/cassandra,bcoverston/cassandra,mshuler/cassandra,swps/cassandra,macintoshio/cassandra,thelastpickle/cassandra,szhou1234/cassandra,weipinghe/cassandra,knifewine/cassandra,ejankan/cassandra,DikangGu/cassandra,mashuai/Cassandra-Research,apache/cassandra,fengshao0907/cassandra-1,hhorii/cassandra,chbatey/cassandra-1,Bj0rnen/cassandra,fengshao0907/cassandra-1,szhou1234/cassandra,Stratio/stratio-cassandra,instaclustr/cassandra,mike-tr-adamson/cassandra,sluk3r/cassandra,Stratio/stratio-cassandra,clohfink/cassandra,ollie314/cassandra,whitepages/cassandra,yangzhe1991/cassandra,ptuckey/cassandra,vaibhi9/cassandra,helena/cassandra,michaelsembwever/cassandra,weideng1/cassandra,aureagle/cassandra,apache/cassandra,sayanh/ViewMaintenanceCassandra,guard163/cassandra,newrelic-forks/cassandra,adejanovski/cassandra,yukim/cassandra,michaelmior/cassandra,DikangGu/cassandra,caidongyun/cassandra,jeffjirsa/cassandra,darach/cassandra,phact/cassandra,hhorii/cassandra,hengxin/cassandra,beobal/cassandra,gdusbabek/cassandra,ptnapoleon/cassandra,RyanMagnusson/cassandra,mike-tr-adamson/cassandra,AtwooTM/cassandra,mkjellman/cassandra,GabrielNicolasAvellaneda/cassandra,jkni/cassandra,chbatey/cassandra-1,ejankan/cassandra,aarushi12002/cassandra,juiceblender/cassandra,ptnapoleon/cassandra,snazy/cassandra,exoscale/cassandra,jrwest/cassandra,ben-manes/cassandra,scaledata/cassandra,kangkot/stratio-cassandra,sharvanath/cassandra,aboudreault/cassandra,vramaswamy456/cassandra,pcmanus/cassandra,mheffner/cassandra-1,yonglehou/cassandra,a-buck/cassandra,codefollower/Cassandra-Research,kgreav/cassandra,driftx/cassandra,vaibhi9/cassandra,bdeggleston/cassandra,kangkot/stratio-cassandra,mt0803/cassandra,nutbunnies/cassandra,scylladb/scylla-tools-java,spodkowinski/cassandra,driftx/cassandra,ptuckey/cassandra,scaledata/cassandra,likaiwalkman/cassandra,szhou1234/cassandra,newrelic-forks/cassandra,GabrielNicolasAvellaneda/cassandra,nitsanw/cassandra,macintoshio/cassandra,Bj0rnen/cassandra,rogerchina/cassandra,bdeggleston/cassandra,hengxin/cassandra,darach/cassandra,tommystendahl/cassandra,sayanh/ViewMaintenanceSupport,chbatey/cassandra-1,jkni/cassandra,iamaleksey/cassandra,thobbs/cassandra,mt0803/cassandra,yanbit/cassandra,driftx/cassandra,strapdata/cassandra,tjake/cassandra,thelastpickle/cassandra,caidongyun/cassandra,gdusbabek/cassandra,Stratio/stratio-cassandra,Instagram/cassandra,blerer/cassandra,emolsson/cassandra,krummas/cassandra,Bj0rnen/cassandra,hengxin/cassandra,jasonwee/cassandra,jkni/cassandra,MasahikoSawada/cassandra,mt0803/cassandra,boneill42/cassandra,josh-mckenzie/cassandra,strapdata/cassandra,pkdevbox/cassandra,mheffner/cassandra-1,blambov/cassandra,wreda/cassandra,jeffjirsa/cassandra,nutbunnies/cassandra,juiceblender/cassandra,yonglehou/cassandra,dkua/cassandra,modempachev4/kassandra,pcn/cassandra-1,aweisberg/cassandra,pkdevbox/cassandra,mheffner/cassandra-1,vaibhi9/cassandra,michaelsembwever/cassandra,jasonstack/cassandra,yhnishi/cassandra,sharvanath/cassandra,wreda/cassandra,guard163/cassandra,codefollower/Cassandra-Research,Imran-C/cassandra,vramaswamy456/cassandra,Jollyplum/cassandra,Jollyplum/cassandra,thelastpickle/cassandra,regispl/cassandra,beobal/cassandra,jbellis/cassandra,ifesdjeen/cassandra,clohfink/cassandra,jasonstack/cassandra,xiongzheng/Cassandra-Research,carlyeks/cassandra,bmel/cassandra,sluk3r/cassandra,jsanda/cassandra,blerer/cassandra,aureagle/cassandra,knifewine/cassandra,xiongzheng/Cassandra-Research,iamaleksey/cassandra,emolsson/cassandra,stef1927/cassandra,bpupadhyaya/cassandra,mshuler/cassandra,cooldoger/cassandra,JeremiahDJordan/cassandra,mkjellman/cassandra,jeromatron/cassandra,RyanMagnusson/cassandra,boneill42/cassandra,wreda/cassandra,pthomaid/cassandra,aarushi12002/cassandra,AtwooTM/cassandra,jasobrown/cassandra,bdeggleston/cassandra,tjake/cassandra,aweisberg/cassandra,rdio/cassandra,DICL/cassandra,belliottsmith/cassandra,Instagram/cassandra,jsanda/cassandra,mshuler/cassandra,kangkot/stratio-cassandra,sayanh/ViewMaintenanceCassandra,blerer/cassandra,bmel/cassandra,mike-tr-adamson/cassandra,yanbit/cassandra,ben-manes/cassandra,nitsanw/cassandra,modempachev4/kassandra,josh-mckenzie/cassandra,rdio/cassandra,ifesdjeen/cassandra,pthomaid/cassandra,regispl/cassandra,apache/cassandra,sivikt/cassandra,scylladb/scylla-tools-java,aboudreault/cassandra,tongjixianing/projects,adelapena/cassandra,Jollyplum/cassandra,jsanda/cassandra,strapdata/cassandra,modempachev4/kassandra,ollie314/cassandra,iburmistrov/Cassandra,tommystendahl/cassandra,whitepages/cassandra,sayanh/ViewMaintenanceCassandra,scylladb/scylla-tools-java,ptuckey/cassandra,macintoshio/cassandra,Imran-C/cassandra,aboudreault/cassandra,hhorii/cassandra,asias/cassandra,jrwest/cassandra,yanbit/cassandra,krummas/cassandra,GabrielNicolasAvellaneda/cassandra,fengshao0907/cassandra-1,nitsanw/cassandra,michaelmior/cassandra,mkjellman/cassandra,scaledata/cassandra,sedulam/CASSANDRA-12201,sivikt/cassandra,a-buck/cassandra,rdio/cassandra,Instagram/cassandra,vramaswamy456/cassandra,dkua/cassandra,yonglehou/cassandra,carlyeks/cassandra,stef1927/cassandra,iamaleksey/cassandra,DICL/cassandra,phact/cassandra,thelastpickle/cassandra,jasobrown/cassandra