Updated configuration.md.
Updated configuration.md.

Review: https://reviews.apache.org/r/49768/

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