Added installation instructions for Ubuntu 14.04 and OS X.
Added installation instructions for Ubuntu 14.04 and OS X.

Review: https://reviews.apache.org/r/34976

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