* Put something on screen
* Use the 32bit watch_date_time repr to pass from JS
* Implement periodic callbacks
* Clear display on enabling
* Hook up watch_set_led_color() to SVG (green-only)
* Make debug output full-width
* Remove default Emscripten canvas
* Implement sleep and button clicks
* Fix time zone conversion bug in beats-time app
* Clean up warnings
* Fix pin levels
* Set time zone to browser value (if available)
* Add basic backup data saving
* Silence format specifier warnings in both targets
* Remove unnecessary, copied files
* Use RTC pointer to clear callbacks (if available)
* Use preprocessor define to avoid hardcoding MOVEMENT_NUM_FACES
* Change each face to const preprocessor definition
* Remove Intl.DateTimeFormat usage
* Update shell.html title, header
* Add touch start/end event handlers on SVG buttons
* Update shell.html
* Update folder structure (shared, simulator, hardware under watch-library)
* Tease out shared components from watch_slcd
* Clean up simulator watch_slcd.c inline JS calls
* Fix missing newlines at end of file
* Add simulator warnings (except format, unused-paremter)
* Implement remaining watch_rtc functions
* Fix button bug on mouse down then drag out
* Implement remaining watch_slcd functions
* Link keyboard events to buttons (for keys A, L, M)
* Rewrite event handling (mouse, touch, keyboard) in C
* Set explicit text UTF-8 charset in shell.html
* Address PR comments
* Remove unused directories from include paths
A simple countdown face using movement_schedule_background_task
so that it rings, even if the another face is active
Limited to 99 minutes and 59 seconds so that the watch isn't staying
out of deep sleep for too long
