Map Rendering; Code Analysis

Improvements to map rendering and fixes for some exceptions that were
being thrown. One was happening because no locking was being done around
the NPC collection. The other was happening because multiple NPCs would
be entering the GFXLoader.TextureFromResource method, and duplicate key
errors would occur in the cache.

Also ran code analysis on the solution.
Disposing

Added cleanup method for GFXLoader that cleans up cached textures. Also
fixed some exceptions being thrown for the newly disposed objects (added
to dispose from code analysis)
Character Stats

The stats page is fully populated, and training works properly.