Improvements to libprocess/README.md.
Improvements to libprocess/README.md.

Review: https://reviews.apache.org/r/35363

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