[doc] Don't refer to non-existing UI item (fixes #630599)
l10n: Updated Greek translation for gcalctool
[l10n] Updated German translation
Fixes for thousand separators and radix points in input, radix points in output

Before, '.' and ',' were always treated as radix points in input. Now
',' is only treated as a radix point if the user's locale specifies it.

If it doesn't, it means you can paste something like "1,574.78".

Before, all numbers were displayed with '.' as their radix point. Now
they respect the user's locale.

The lexer was also reformatted to have roughly 1 order of magnitude fewer
states.
Revert parts of last commit

I was a bit too optimistic, and managed to disable irrelevant
functionality like 1+1. Oops!
Updated Brazilian Portuguese translation
Updated Catalan translation
Revert most of the previous parser changes, as they caused regressions
nl_langinfo returns empty string, not NULL, when no value exists
Fixes to work with latest GTK3

https://bugzilla.gnome.org/show_bug.cgi?id=630115
Bump GTK dependency, make GTK+3 default
Updated Lithuanian translation by Aurimas Černius <aurisc4@gmail.com>
Updated Lithuanian translation by Aurimas Černius <aurisc4@gmail.com> and Rimas Kudelis <rq@akl.lt>
Add string serializer class from parts of mp-convert and math-equation

Put back thousands separators support, fixes #628908
Remove deprecated has_separator properties from GtkBuilder files
Add missing G_END_DECLS macros
Make window resizable again (#630594)
Adjust ui file to resizability
Add enum type templates to source distributions
Version 5.91.0