Updated Japanese translation
2.1.26 beta
Merge pull request #1809 from t61p/japanese-translation

Updated Japanese translation
Updated changelog
Updated compatibility section
Showing stored version in about
Updated support section
Updated support section
Remember on demand dialog settings across reboots

Fixes #1812
Updated upgrading section
Updated Italian translation
Removed function help from on demand dialog
Displaying less details in on demand dialog in expert mode