[Tuxpaint-i18n] Brushes may have [localized] descriptions

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

I've finally added a small feature that allows brushes to
have descriptions that appear (rather than generic instructions)
when you select them.

This is being handled basically identically to how Stamp
descriptions are handled.  Each brush may have an optional
".txt" file which includes the description in a variety of
languages.

A pair of scripts (cribbed from `tuxpaint-stamps`) are used
to sync the text in these files with some new PO files and
a POT file.

If you'd like to translate them, you can see the new
file "tuxpaint-brushes.pot" inside the main "tuxpaint"
source code repository, under a new "brushes-po" subdirectory:

  https://sourceforge.net/p/tuxpaint/tuxpaint/ci/master/tree/brushes-po/

Links to the files, and the translation statistics for this
new domain, are also available on the "Help Us Translate"
page of the website:

  https://tuxpaint.org/help/po/#tpb

(It's only 15 strings, and I don't expect it to get much
larger any time soon.)

Thanks!

-- 
-bill!
Sent from my computer