Advanced journal, dialogue history rewrite

Dialogue history was rewritten to use the new text rendering and keyword search modules. This fixes http://bugs.openmw.org/issues/537 , http://bugs.openmw.org/issues/733 and removes a lot of ugly code.

There's a couple minor journal issues left, which might be non-trivial to solve, I would add separate issues to the tracker for them if this gets merged.

 - [Journal backend] Quest names are unavailable (index shows id, pages show nothing)
 - [Journal backend] The name of the NPC that spoke on a particular topic is not available
 - [Journal backend] Quest completion status unavailable

 - Extra space in front of topic links. There is only report of this happening, not sure what causes it

 - Possible performance issue for big journals, since the layout is recreated every time the journal is opened. In a quick test, 14 pages took 4ms.