PEP8 fixes.
Merge pull request #76 from johngian/pep8-fixes

PEP8 fixes.
Add addressed field in question.
Remove 'safe' from templates.
Merge pull request #81 from akatsoulas/monkey-patch-jingo

Remove 'safe' from templates.
Add ribbon for answered questions.
Merge pull request #83 from akatsoulas/address-question

Add ribbon for answered questions.
Add reveal.js lib.
Admin replies to questions functionality.

* Add reply form only for admins.
* Show replies in replied questions.
* Add datamigration for "Admin" group.
* Add reply field in questions.
Do not use underscore in classes.
Show only archived events in archive.
Merge pull request #80 from akatsoulas/admin-answer-77

Fixes and new functionality