Use app_id with github

The basics of authenticating to github as an app when posting
comments and cloning. This is still a WIP.

Change-Id: I11fab75d635a8bcea7210945df4071bf51d7d3f2
diff --git a/requirements.txt b/requirements.txt
index 3bb7f91..48ac38e 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -24,3 +24,5 @@
 alembic
 cryptography>=1.6
 cachecontrol
+pyjwt
+iso8601