Don't use relative imports like `../foo.h` as those depend on the
relative position of both files. Rather than that use imports relative
to the `src` directory, which explicitly is part of the include
directories.
* add submodule littlefs
* base fs
* Save settings using littlefs
* Small fixes and suggestions from PR
* More small fixes from PR suggestions
* Code clean up
* Change SpiNorFlash functions to be private in FS
new navigation
add some color to the apps
redesign menus
new settings menu
new quick settings
code clean up
size reduction by converting navigation images to font
and more...