New:
line and triangle primitives
message popup dialog
expose buttons for for font, alignment, color, timer, switch and source pickers
generic popup dialog that can be filled with other things
lvgl.isAppMode() function to let widgets know when app mode is active
additional containers for creating layouts (box and setting)
flex layouts
Fixes:
colors are updated when theme changes
fix memory leaks when stand alone scripts close
run stand alone scripts in a separate Lua state and use lua_pcallk() to prevent cross boundary errors (color only)
* Store 'zone' rectangle dat in Lua registry and update it when the screen layout changes or full screen mode changes. Allows Lua widgets to adjust to layout changes.
* Call widget 'update' function is layout has changed.
