Added legacy link support for BBCode. Fixes #120
[JRO] Add spec for [link]
[/link] bbcode
[SMB] Adds FTS to topic.title

* Reworked search parser to return key => values to avoid having to do it later. Updated tests to reflect changes
* Refactored search sql builders to have less duplication
* Fixes bug where user and category ids were being calculated multiple times
[#115] WIP. Sign in/up from a topic

TODO: Needs some test coverage after this code spike
WIP
WIP