Added containerizer option to mesos-execute.
Added containerizer option to mesos-execute.

Review: https://reviews.apache.org/r/40371

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