contrib_bots: Expose some information about user profile

- Expose some information about user profile in `RestrictedClient`
class, like `full_name` and `email` of the user.

- Add `client` argument to `triage_message()`, now it's possible to
call bot with another method instead of calling the specified
keyword.

contrib_bots/lib/github_issues.py

@@ -52,7 +52,7 @@ class IssueHandler(object):
             github_token    (The personal access token for the github bot)
             '''
 
-    def triage_message(self, message):
+    def triage_message(self, message, client):
         # return True if we want to (possibly) respond to this message
         original_content = message['content']
         # This next line of code is defensive, as we