v8.5.4.kt.14

• added ifShortcut command which simplifies binding custom shortcuts
• added final modifier which substitutes break, allowing simple if/else branches to be written inline
• implement shortcut parser which allows referencing non-ascii scancodes from macroes
• refactored layer switching - introduced unToggleLayer/ToggleLayer commands which should replace the switchLayer commands. Toggle commands respect toggling and holding semantics and (for instance) allow untoggling toggled layers by shortcuts held via "held" layers.
• Changed semantics of 'previous' for the hold/toggling commands - "previous" layer can now be "held", i.e., pushed onto stack instead of removing stack top.
• single-runtime-macro-length limited to 1/4 of macro memory. This prevents unwanted overwriting of old macroes e.g., by leaving the recorder running.