Updated CHANGELOG for 0.26.1-rc1 release.
Updated CHANGELOG for 0.26.1-rc1 release.

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