When selecting a label that has a color not found in the built-ins,
we change to the color picker; however, when rendering its button,
it looked wrong and would not fit to the right size (had 48x48
hard-coder in there, still!) Instead, using `render_color_button()`
to just re-render it.
Also, dropping LOW_QUALITY_COLOR_SELECTOR which had been used by
some embedded platforms we don't seem to support any more (Nokia Maemo
and OLPC XO-1).
Some already-translated (but very out-of-date) content
has been replaced with not-yet-translated (i.e., English) content.
Translators may want to look at the previous revisions of these
files when translating the new 'tuxpaint-docs' gettext catalog.
Sorry to cause extra work here, if I've done so.
