PICO-8 v0.2.0h compatiblity roadmap

[samhocevar]

• Added: tline() takes an optional layers parameter, similar to map()
• Added: high bits of 0x5f5e taken as colour read mask, low taken to be colour write mask
• Added: Double-click in the sfx tracker to select all attributes of a single note.
• Fixed: assignment shorthand RHS scope wrong when contains certain operators. e.g. a+=1&127
• Fixed: while/if shorthands fail when "do" or "then" appears on the same line as part of an identifier
• Fixed: ctrl-c copies the wrong sfx after clicking pencil button (next to pattern #) in organiser view
• Fixed: spinning cart icon present in video memory when cart boots from splore