Alpha 12 dev-2664

Bug Fixes

 * Fixed several bugs preventing items (particularly windows) from being placed.
 * Fixed bug that prevented placing multiple items in succession from the place item window.
 * Fixed error 'invalid normal in normal_to_rotation' when trying to place items.
 * Fixed resource leak that was preventing threads and datastores from getting cleaned up.
 * Fixed engine error caused by save/load while shepherding.
 * Fixed UI error when closing the new game dialog.

Other Changes

 * Added slider to Settings->Gameplay to control the maximum number of citizens in a town. If you are experiencing idle hearthling issues, try lowering this limit.
 * Reduced the maximum density of animals in a shepherd's pasture.
 * Reduced memory usage of the game.