Merge pull request #5 from dennwc/gplus

Google+ provider
Add GetProviderName function as variable
Merge pull request #7 from tylerb/master

Add GetProviderName function as variable
Remove context clear calls
Merge pull request #9 from tylerb/master

Remove context clear calls
update gplus scopes
satisfy golint
fix improperly named receivers
un-export internal variables
fix poorly named receivers
Add missing comment
Add github provider

Fix #2
Merge pull request #11 from tylerb/master

Update gplus scopes. General cleanup.
Merge branch 'github'
Merge branch 'master' of github.com:markbates/goth
Merge pull request #13 from tylerb/master

Add Github provider
Merge pull request #1 from markbates/master

Merge upstream