feat(web): Add option useAlerts to control alerts()

feat(web): Update addLanguageKeyboards to return a Promise

fix(linux): fix tab completion for command line tools

fix(linux): Don't add duplicate entries when reinstalling keyboard

fix(windows): osk scaling mismatch on horz axis

* Add more description on promise-api/index.html
* Use OptionType

auto: increment master version to 15.0.75

When we update/reinstall an existing keyboard we don't want to
add a new entry to the list of keyboards.

Fixes #5308.

fix(linux): Add libglib2.0-bin to keyman Depends 🍒

Fixes #5306

Fixes #5344

(cherry picked from commit 12e2c4c2)

feat(linux): Add support for impish (Ubuntu 21.10)

feat(common/core/web): engine correction-prep optimizations

fix(android): fixes application of nextlayer for subkeys with customized layer setting

auto: increment master version to 15.0.74

fix(linux): Improve error handling if `lang_tags_map.py` is missing

If the developer forgot to run `make` to create `lang_tags_map.py`
we now print a message instead of reporting to Sentry.

Fixes #5343

Font scaling on individual keys would ignore the vertical axis if the
horizontal axis reached the key width threshold, rather than calculating
the minimum of the two axes. This lead to weird effects, such as adding
characters to a key could make the font larger rather than smaller!

Reported by @jmdurdin.

feat(linux): Auto-generate reference help

Co-authored-by: Marc Durdin <marc@durdin.net>

chore(windows): add engine test framework

This is a rudimentary start to having unit tests for keyman32.

At present, it will build only in win32/debug and requires you
to manually run make -DDEBUG beforehand. The tests currently
run in Visual Studio and are not integrated.

auto: increment master version to 15.0.73