- put a filter model in place, so only the themes with "show" set
are displayed
- rip out the messing about with widgets, soon to introduce a model-
based UI
- point to main Calamares site in the 'part of' headers instead
of to github (this is the "this file is part of Calamares"
opening line for most files).
- remove boilerplate from all source files, CMake modules and completions,
this is the 3-paragraph summary of the GPL-3.0-or-later, which has
a meaning entirely covered by the SPDX tag.
- This enables working in three modes:
- No themes listed; all are shown without screenshots,
- Themes listed, showAll false; only those are shown,
- Themes listed, showAll true; the installed-but-not-listed
themes are shown after the listed ones, and have limited info.
- For OEM modes where there is already a theme, add a preselect:
key to pick a specific theme and have that one come up as already-
selected in the list.
- Don't re-run the lnftool if an already-selected theme is clicked
again. Use toggled() instead of clicked().
