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Minor code clean-up
pdFont: new functions needed for new UCs
Updated German language file from Helmut

Very grateful for his expert work in helping maximize the quality of our
German translation.  He's still working on the latest 6.4 updates, but
I'd like to back up his original version in the meantime.
New "ButtonStrip" user control

This UC proved to be more of a challenge than I first expected.  After a
number of rewrites to improve its interface, appearance, and overall
behavior, I think I'm finally satisfied enough to commit it.  (Some work
is left to be done, but this is a good starting point.)

Besides modernizing PD's interface (always nice!) and fully integrating
with PD's theming engine (also nice!) and fully supporting Unicode
(yay!), I'll soon be adding image support to this.  This will allow the
UC to not just replace radio button occurrences, but also replace
category buttons like the channel buttons used in the Curves dialog.

Similarly, in some of PD's more complicated effect dialogs, I'd like to
use this like a tab control, and have it toggle separate "basic" and
"advanced" panels, which could greatly improve usability of some of PD's
more crowded dialogs.

Aside from image support, a few other to-do items remain (tooltips and
focus handling in particular).  Like many other custom UCs in PD,
animation support would also be great in the future, but I've held off
implementing that until I have a good framework for it.

Also of note: translation support is already active and working, and the
translation generator will auto-grab text from this new UC using the
same pattern matching it uses for drop-down and list boxes.
Add live interface change support for the new button strip UC
Add translation support for the new button strip UC
Blur > Zoom Blur: trial implementation of new button strip UC

Good-bye radio buttons, hello button strip!

Note that the new control's initialization behavior is identical to a
drop-down or list box, e.g. use of "AddItem" and "ListIndex".  After
testing a few different techniques, this became my preferred
implementation, in part because it plays very nicely with PD's master
translation file generator (e.g. no changes required to support
translations on these UCs).

No support is currently provided for modifying or removing buttons, as I
have no need for it.