Fixed a couple of bugs in the movement/collision system.
Pushable blocks now ignore blocks which are disabled.
Fixed a bug where the player was incorrectly squashed when (mostly) standing on a moving block that moves at the speed of one and the player hits a resting pushable block.
Also fixed a bug where the wrong block is chosen for lastStand when falling and intersecting with two blocks of which the lower one has an upwards velocity causing an incorrect squash the next frame by checking the 'depth' of the colliding blocks.