[DBAL-42] Optimized column comment change detection. Ignore from columns with a null comment which indicates not set compared to an empty string which says delete comment.
[DBAL-42] Optimized column comment change detection. Ignore from columns with a null comment which indicates not set compared to an empty string which says delete comment.

tk-s/dbal,adrienbrault/dbal,stchr/dbal,gencer/dbal,stof/dbal,zeroedin-bill/dbal,LionwareSolutions/dbal,adrienbrault/dbal,wuxu92/dbal,easybiblabs/dbal,kupishkis/dbal,vutung2311/dbal,mariuz/dbal,cassvail/dbal,sarcher/dbal,hason/dbal,mihai-stancu/dbal,webmozart/doctrine-dbal,vortgo/dbal,stof/dbal,hason/dbal,mbeccati/dbal,mikeSimonson/dbal,stchr/dbal,BenMorel/dbal,bspeterson/dbal,easybiblabs/dbal,mRoca/dbal,arima-ryunosuke/dbal,adrienbrault/dbal,tk-s/dbal,PureBilling/dbal,BenMorel/dbal,kimhemsoe/dbal,shivergard/dbal,mRoca/dbal,easybiblabs/dbal,LionwareSolutions/dbal,kimhemsoe/dbal,arima-ryunosuke/dbal,Tobion/dbal,PowerKiKi/dbal,sarcher/dbal,LionwareSolutions/dbal,Tobion/dbal,webonyx/dbal,mbeccati/dbal,drieschel/dbal,webonyx/dbal,arima-ryunosuke/dbal,nfrignani/dbal,mariuz/dbal,vortgo/dbal,PowerKiKi/dbal,v-bartusevicius/dbal,PureBilling/dbal,mihai-stancu/doctrine-dbal,DHager/dbal,webonyx/dbal,DHager/dbal,doctrine/dbal,kupishkis/dbal,bspeterson/dbal,deeky666/dbal,mihai-stancu/dbal,drieschel/dbal,kupishkis/dbal,lcobucci/dbal,v-bartusevicius/dbal,nfrignani/dbal,shivergard/dbal,lafourchette/dbal,sarcher/dbal,Ocramius/dbal,PowerKiKi/dbal,mathroc/dbal,helicon-os/doctrine-dbal,gencer/dbal,helicon-os/doctrine-dbal,deeky666/dbal,AlexDpy/dbal,janschoenherr/dbal,lafourchette/dbal,DataSyntax/dbal,zeroedin-bill/dbal,mariuz/dbal,doctrine/dbal,wuxu92/dbal,janschoenherr/dbal,AlexDpy/dbal,hason/dbal,cassvail/dbal,vutung2311/dbal,DataSyntax/dbal,Ocramius/dbal,mikeSimonson/dbal,mihai-stancu/doctrine-dbal,lcobucci/dbal,mathroc/dbal