MERGE these: Some bugfixes - the buildsystem is acting up again

See merge request Librem5/squeekboard!53

FINAL: bundle xml resources, allows running uninstalled from git repo

Closes #29 and #21

See merge request Librem5/squeekboard!49

gitlab-ci: No need for our ci repository

See merge request Librem5/squeekboard!54

Just using debian buster makes things more stable.

This let's us drop the virtboard build dependency.

This allows running uninstalled from a git repo

Closes: #21, #29

- remove bounds it is not used.

- remove the g_clear_pointer, it does the same thing as the if-block
  above, the were both there as the result of the merge, and it is
  apparently easily overlooked

- cleanup after myself (FIXMEs)

Implement basic keyboard views

See merge request Librem5/squeekboard!51

Use existing concepts of levels and modifier latches and locks to
implement the three view design of issue #38.

The use of a lock to switch from letter to numbers and a latch to
handle upper and lower case has side effects, but these can be
addressed in a future commit.

Specify a keyval to make the backspace key work again

Closes #45

See merge request Librem5/squeekboard!50

Update symbols to more closely resemble #38

See merge request Librem5/squeekboard!48

Drop now unused theme_path

See merge request Librem5/squeekboard!46

Use an icon for backspace

See merge request Librem5/squeekboard!47

Add some border at the top

Closes #28

See merge request Librem5/squeekboard!43

Use a gresource to store the css

See merge request Librem5/squeekboard!28

# Conflicts:
#   src/server-context-service.c

Closes: #28

Remove unused color definitions

See merge request Librem5/squeekboard!42

Remove currently unused eekboard code

See merge request Librem5/squeekboard!41

Remove unlisted files

See merge request Librem5/squeekboard!38

Some cleanups, and some FIXME hints for future work (no functional changes)

See merge request Librem5/squeekboard!39

Prevent compiler warnings by commenting out unused code

See merge request Librem5/squeekboard!37

brief, clear, idiomatic and grep friendly