Added 1.0 changes to upgrades.md.
Added 1.0 changes to upgrades.md.

Mesos 1.0 changes need to be reflected in upgrades.md.

Review: https://reviews.apache.org/r/48272/

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