Added faker and pry-rails
Added factories for creating Players and Citys along with their sub children
Added MOVE_UNIT constant to refer to move unit action
GameState.advance_turn can optionally only run a single state modifier; failing spec for moving units
Marked can process a move turn as pending
Extracted state modifer filtering out to private method
Merge pull request #16 from RantGames/move_units

Move units