Merge pull request #570 from nelenkov/master

backported fix for #562 to master
Merge pull request #582 from nelenkov/master

backported OAuth authenticator
Update README.md

Add link to alpha/beta versions and note that nightly builds are out of date
Update README.md
Merge pull request #591 from nelenkov/master

Merged dev and bumped to 2.6
added back full changelog