added support for multiple game layers
changed name of game layer type member
Merge branch 'dd_cb_gamelayers' into dd_cb_triggertiles

 is necessary,
fixed brush grabbing
Merge branch 'dd_cb_gamelayers' into dd_cb_triggertiles
fixed weird last commit
Merge branch 'dd_cb_gamelayers' into dd_cb_triggertiles
fixed client random layers bug
Merge branch 'dd_cb_gamelayers' into dd_cb_triggertiles
fixed bug with trigger tiles
fixed tiles outside of map
Merge branch 'dd_cb_triggertiles' into dd_fb_switches

Conflicts:
	src/game/collision.cpp
	src/game/collision.h
added images and buttons for switches