rewrite all the things

This is super ready to go.

This is a huge revamp of literally everything. It includes:

- A rewrite of the ADN client (we should extract this into a separate package at
  some point)

- A move to Silex for all routing needs

- Removing all the old adnlib code

- Using Twig to render all HTML

- Using data transfer objects everywhere instead of arrays

Closes #31, closes #32.

Todo:

Nice-to-have:

- [ ] Document folder structure
- [ ] Add docblocks to every class, method
- [ ] Re-add Orphan Black post club code

Done:

- [x] Following Comparison tool
- [x] First Mention tool
- [x] Broadcast Channel Lookup tool
- [x] User lookup page
- [x] Signin
- [x] Signout
- [x] Homepage
- [x] About page
- [x] Donate page
- [x] Terms page
- [x] Privacy page
- [x] Broadcast tools overview page