front end changes to handle None from the datastore
Merge pull request #239 from anubhavsinha/#233_fron_end_changes

front end changes to handle None from the datastore
Fixing exception when viewing challenge page

while not logged in (fixes #171).
Merge pull request #243 from egor83/master

Fixing exception when viewing challenge page while not logged in (fixes #171).
Fixing unit tests problem (#232)
Merge branch 'master' into voting
Unit tests for voting: RPC handler (#121).