Revert "Removed chatter from travis.yml"

This reverts commit a58c069f1b5df8a13c986c017ae216c6190ec161.
add support for state oauth param

Need to use the state oauth param so that after authentication you can
specify the location that you were trying to get to before being
redirected to oauth.  The state should be set in the controller where
you initiate the oauth.
Merge branch 'master' of https://github.com/developerforce/Force.com-Toolkit-for-NET