v0.0.6 (Moorgate) Preview builds available

This release is a bigfix release - after releasing v0.0.5 I started systematically playing through all the levels, and along the way found a slightly embarrassing number of bugs that needed fixing:

• Fixed a problem where Barriers did not correctly load their settings from the level file. This meant they did not listen on the correct signal, so some barriers could never be opened.
• Fixed time bomb behaviour to destroy floors around them if possible when the time bomb explodes.
• Fixed Inode collision settings so they can be destroyed and set off proximity mines.
• Fixed the behaviour of Reflector blocks so that they always reflect beams back to where the beam came from, rather than off to the side under some circumstances.
• Fix the “Whirlpool” level so it can be completed.

This update also adds a tooltip system to the main game user interface to indicate what each button does when the mouse hovers over it.