Return audit from approval function
Use a datetime/instance instead of just a date on audit records
Fix a bug where updates would get counted twice

If a field is a "pending field" then it should be logically removed from
the fields that are being marked as "updated"
Encode only primitive types when converting audit to dict
Add in recent edits API endpoint and tests
Set the default vagrant box to precise64

We will be developing on and deploying to exclusively 64-bit machines.
Merge pull request #31 from ahinz/topic/recent-edits-api

Topic/recent edits api
Merge pull request #33 from jwalgran/topic/default-64

Set the default vagrant box to precise64