[Tuxpaint-i18n] New perspective drawing tools & complexity setting

[Bill K. <nb...@so...>]

Hi all, and happy new year!

Just a heads-up that some development for the next version of
Tux Paint has been done, and I've added a set of new drawing
tools for drawing in 1-Point, 2-Point, and 3-Point perspective,
as well as adjusting/positioning vanishing points.

Further to that, I've added a new "complexity" setting, that
allows a user to specify their expertise level with Tux Paint
(or art software, or computers in general), which allows some
Magic tools to behave differently.

For example, the perspective drawing tools mentioned above will
normally (in the default "advanced" complexity mode) appear as
six different magic tools: three for drawing, and three for
adjusting their respective vanishing point(s).

However, in "beginner" mode, only drawing tools will be made
available; you're stuck with the default vanishing points.
In fact, a fourth drawing tool, an alterlative version of the
3-point perspective, will be made available in this case.
(One for drawings "looking up from below", and the alternative
for "looking down from above".)

Lots of strings have been added (or in some cases changed) based
on this work, and a bunch of other things I've done recently *,
so if you've got the time & interest, please grab the latest
PO files and send me (or commit back, if you have Git access)
updates.

Thanks as always, and take care!  Wishing you all the best for 2024,

-bill!

* All over the place: `tuxpaint`, `tuxpaint-docs`, `tuxpaint-website`,
  `tuxpaint-config` repos.  See https://tuxpaint.org/help/po as always.