Changed -j8 to -j6 in the docker build to avoid g++ OOMs in CI.
Changed -j8 to -j6 in the docker build to avoid g++ OOMs in CI.

Gilbert88/mesos,asamerh4/mesos,Aman-Jain-14/customizedMesos,verizonlabs/mesos,neilconway/mesos,andschwa/mesos,gsantovena/mesos,yuquanshan/customizedMesos,gsantovena/mesos,andschwa/mesos,abudnik/mesos,craimbert/mesos,kaysoky/mesos,abudnik/mesos,kaysoky/mesos,asamerh4/mesos,andschwa/mesos,chhsia0/mesos,yuquanshan/customizedMesos,andschwa/mesos,gsantovena/mesos,chhsia0/mesos,yuquanshan/customizedMesos,abudnik/mesos,chhsia0/mesos,asamerh4/mesos,neilconway/mesos,andschwa/mesos,abudnik/mesos,reneploetz/mesos,dforsyth/mesos,neilconway/mesos,craimbert/mesos,kaysoky/mesos,verizonlabs/mesos,yuquanshan/customizedMesos,abudnik/mesos,Aman-Jain-14/customizedMesos,yuquanshan/customizedMesos,verizonlabs/mesos,abudnik/mesos,yuquanshan/customizedMesos,neilconway/mesos,chhsia0/mesos,kaysoky/mesos,reneploetz/mesos,kaysoky/mesos,jpeach/mesos,verizonlabs/mesos,zmalik/mesos,Aman-Jain-14/customizedMesos,jpeach/mesos,andschwa/mesos,jpeach/mesos,zmalik/mesos,gsantovena/mesos,gsantovena/mesos,reneploetz/mesos,Aman-Jain-14/customizedMesos,neilconway/mesos,reneploetz/mesos,zmalik/mesos,chhsia0/mesos,dforsyth/mesos,craimbert/mesos,yuquanshan/customizedMesos,zmalik/mesos,Gilbert88/mesos,jpeach/mesos,andschwa/mesos,jpeach/mesos,gsantovena/mesos,Gilbert88/mesos,Aman-Jain-14/customizedMesos,dforsyth/mesos,chhsia0/mesos,jpeach/mesos,craimbert/mesos,Gilbert88/mesos,dforsyth/mesos,Aman-Jain-14/customizedMesos,asamerh4/mesos,jpeach/mesos,craimbert/mesos,asamerh4/mesos,gsantovena/mesos,zmalik/mesos,zmalik/mesos,kaysoky/mesos,zmalik/mesos,Aman-Jain-14/customizedMesos,verizonlabs/mesos,Gilbert88/mesos,reneploetz/mesos,verizonlabs/mesos,abudnik/mesos,chhsia0/mesos,reneploetz/mesos,craimbert/mesos,asamerh4/mesos,dforsyth/mesos,dforsyth/mesos,verizonlabs/mesos,Gilbert88/mesos,neilconway/mesos,asamerh4/mesos,reneploetz/mesos,Gilbert88/mesos,kaysoky/mesos,dforsyth/mesos,neilconway/mesos,craimbert/mesos