Fixes #4013, Caches vanish from lists when storing them
Update cheangelog
Fixes #4025, Usage of Mytery instead of Unknown in GPX exports

- makes 'Unknown Cache' again the main type, still understanding 'Mystery Cache'
Update changelog_release.xml
Fixes #4012, Search result limited to 40 caches

- meanwhile keeping the original query parameters seems not only to be possible but even necessary
fix #4036: avatar not shown on gc.com login
Update changelog_release.xml
Update AndroidManifest