Updated map system (read more)

Project compiles and runs, multiplayer works, but the map is not visible

There are a number of major changes to the map system, beth directly from the
jam branch and from the splicing process. The changes that are listed here have
been noted as they were added to the index for committing.

* tile_sheet.*pp moved from 'common/graphics/' to 'common/map/'
* Minor method and member name changes to TileSheet
* TileSheet has a lua API, but it isn't used anywhere
    NOTE: Nothing uses both lua and graphics, but a theoretical editor might
* Region API's glue functions have been changed from triggers to simple dummy
    methods. These should simply be over written.
* RegionPagerBase::GetRegion(int x, int y) now snaps it's parameters
    Presicely why is unknown, but I do remember there was a bug without it
* RegionPagerLua has been rewritten to use the Region API's methods, rather
    than the triggers.
* RegionPagerLua no longer stores the map's save directory, or passes it to the
    the Region API's methods.
* RegionPagerLua::luaState renamed to RegionPagerLua::lua
    conforms to changes elsewhere
* Removed the directory glue functions from the RegionPager API
* region_pager_api.hpp preprocessor guard changed
* Adjusted makefiles to account for TileSheet's movement