Redux: Save user's Google avatar if they have one

PyMongo 3.0

use datetime.datetime.utcnow() to create timestamps

closes #27

ENH: Refactor module

Expanded upon the Group's regex patterns.

Both _id and name now require a letter or number at the start and end, and enforce the minimum and maximum length.

Fix arbitrary path access

Optional NewRelic support

Zipfiles, mark 2