fix #4359: imperial units checkbox not always correct

This has been fixed by initializing the key to its default value instead
of just the checkbox. Also, better names have been used throughout the
settings to reflect the fact that "units" meant "use imperial units". It
was used in both ways, including the wrong way while migrating the
settings.
fix #4341: captcha doesn't refresh
Merge branch 'release' into upstream

Conflicts:
	main/src/cgeo/geocaching/connector/gc/RecaptchaHandler.java
Merge branch 'issue-4260' into release
Merge branch 'release' into upstream
fix #4291: keyboard should stay hidden when showcase is visible
Merge branch 'release' into upstream
Minor cleanup
fix #4330: uploading waypoint is shown although not uploading
Merge branch 'issue-4330' into upstream
Update changelog_release.xml
Add code documentation for local spoilers usage
Merge branch 'release' into upstream
crowdin: New translations
Merge branch 'release' into upstream

Conflicts:
	main/res/values-da/strings.xml
Small update for README
mf 0.4 wip
mf 04 wip 2
mf 0.4 wip 3