(It's still leaking into BOARD_COMMIT and some other places, but at
least it no longer leaks into all the edit tools.)
Also fixes some bugs when moving/copying/pasting multiple selections
containing length-tuning patterns.
Using a boolean argument just leads to a lot of trailing booleans in the
function calls and is not user friendly. Instead, introduce PostAction()
to send an action that runs after the coroutine (equivalent to passing
false or the default argument), and leave RunAction as the immediate
execution function.
Bitmaps are now identified by an enum class instead of by pointers.
Bitmap loading and caching is now handled by a class in common, and
we no longer compile most bitmaps into the binary, so there is no
longer a bitmaps static library.
Instead, bitmaps are archived to a .tar.gz file which is installed
in ${KICAD_DATA}/resources/images.tar.gz
The source PNGs are checked in to Git as the original CPP files were,
so that people can build without the required dependencies to convert
SVGs to PNGs.
Initial support is also added for dark theme icons, although this
is not yet exposed in the GUI.
Stubs are present for multi-resolution image resources, but this is
not fully-baked yet and could use some refinement.