fixed scope for user email

scope to request user email is "user:email" not "email"

See: https://developer.github.com/v3/oauth/#scopes
Merge commit 'cf45fb38cf43902013a0cc2ef34f42a277f461e4' into patch-1
added scope for all environments.
Merge pull request #32 from jadar/patch-1

fixed scope for user email