* New doodads: Switches.
* They come in four varieties: wall switch (background element, with
"ON/OFF" text) and three side-profile switches for the floor, left
or right walls.
* On collision with the player, they flip their state from "OFF" to
"ON" or vice versa. If the player walks away and then collides
again, the switch flips again.
* Can be used to open/close Electric Doors when turned on/off. Their
default state is "off"
* If a switch receives a power signal from another linked switch, it
sets its own state to match. So, two "on/off" switches that are
connected to a door AND to each other will both flip on/off when one
of them flips.
* Update the Level Collision logic to support Decoration, Fire and Water
pixel collisions.
* Previously, ALL pixels in the level were acting as though solid.
* Non-solid pixels don't count for collision detection, but their
attributes (fire and water) are collected and returned.
* Updated the MenuScene to support loading a map file in Play Mode
instead of Edit Mode. Updated the title screen menu to add a button
for playing levels instead of editing them.
* Wrote some documentation.
* Add the other trapdoor directions: Left, Right and Up.
* UI: Show a color square in each Palette Swatch button in Edit Mode.
* Instead of just the label like "solid", "fire", "decoration" it also
shows a square box colored as the swatch color. The label and box
are left-aligned in the button.
* Minor Play Mode physics update:
* The player jump is now limited: they may only continue to move
upwards for 20 ticks, after which they must touch ground before
jumping again.
* Remove the "press Down to move down" button. Only gravity moves you
down.
* Fix a crash in the Editor Mode when you dragged doodads on top of each
other. Source of bug was the loopActorCollision() function, which only
should be useful to Play Mode, and it expected the scripting engine to
be attached to the Canvas. In EditorMode there is no scripting engine.
* Debug mode: no longer enables the DebugOverlay (F3) by default, but
does now insert the current FPS counter into the window title bar.
* ui.Frame: set a default "mostly transparent" BG color so the frame
background doesn't render as white.
* Add the MenuScene which will house the game's main menus.
* The "New Level" menu is first to be added.
* UI lets you pick Page Type and Wallpaper using radio buttons.
* Page Type: Unbounded, Bounded (default), No Negative Space, Bordered
* Fix bugs in uix.Canvas to fully support all these page types.
* Implement the handler code for `return false` when actors are
colliding with each other and wish to act like solid walls.
* The locked doors will `return false` when they're closed and the
colliding actor does not have the matching key.
* Add arbitrary key/value storage to Actors. The colored keys will set
an actor value "key:%TITLE%" on the one who touched the key before
destroying itself. The colored doors check that key when touched to
decide whether to open.
* The trapdoor now only opens if you're touching it from the top (your
overlap box Y value is 0), but if you touch it from below and the door
is closed, it acts like a solid object.
