Update README.md
Cleaned up MapLoader a little
Moved get/setRoom up to Entity

Sinve most (if not all) Entites will be inside of a room at some point
it makes sense to move this up int the heirarchy. This allows
construction of objects lower in the hierarchy by supplying a nullptr as
the "room" which can be set (or not?) later.
Created ItemFactory (but it still needs work!)

This is a basic inferface for an ItemFactory but all of the construction
hard coded. I want to defer the construction to somewhere else but for
now this will do. Eventually this will work by cloning prototypes but
for now hard-coding gets us rolling.
Testing the ItemFactory in MapTestState

Replaced the Item creation by calling the factory method. It works!
Added ignore path for jsoncpp in .gitignore
Added jsoncpp submodule
Added jsoncpp folder
Merge pull request #22 from zackthehuman/master

Code cleanup, added ItemFactory, added jsoncpp source files