Move JSON representation management to the model classes

Most model classes now have a _json(extended=False) method that returns a JSON
serialize-able representation of the class. Some objects have a short and long
representation (ex: Requests' long representation includes all Actions and
Modifiers).
Rewrite/restyle payout listing

More detail is given, allowing payers to verify the request has been processed appropriately. The payouts listing now also infini-scrolls, with new requests being added (and old ones being updated in case more than one payer is working on the list). The minimum time between list updates is currently 7 seconds, but that value may be revisited later. Individual entries also get updated when any of their copy buttons get activated.

Addresses #49, #65
Add transformer links to the extended JSON form of Requests

This allow the request detail page and payout listings to show/update the transformed attributes. The constellation and region attributes were also added to the standard JSON output.
Default to the first choice when changing a Request's division

Resolves #70
Fix modifier evaluation when setting a new payout

Continuation of the problem fixed in 94c62acd1f95215a6d91b105d6eb50d1fa6f5215.

Resolves #69
Discard ordering when summing a list's payouts

Ordering was changing the calculated sum to be too low (and occasionally too high). I'm not sure why it was doing this, but removing ordering solves the problem.
Static files can now use a hash to avoid caching problems

By using the versioned_static helper in Jinja, static file URLs will have an 8 character hash of their contents inserted before the file extension. This should help avoid problems with old versions of static assets being held in external caches for too long.
Add an AnonymousUser class with has_permission

Fixes cases where an anonymous user tries to submit a request.
Fix Killmail validation test to log in a user beforehand
Refactor request listing tests to account for payout mode's new format