Failsafe for loading ListIndex presets outside the range of their parent combo box
Still more resize form UI adjustments (and misc bugfixes)

For the life of me, I cannot settle on a proper resize UI.

Adobe's latest resize dialog is actually quite lovely
(http://helpx.adobe.com/photoshop/using/resizing-image.html).
Relatively minimalist while exposing a lot of features, including a
preview.  Previews are on the map for PD's resize, but they're a bit
hairy to implement, so I'm holding off for now.

Anyway, my latest resize dialog layout is heavily inspired by Adobe's
UI.  I've removed advanced resize options for now because as clever as
they are, I cannot find a good way to implement them in this main resize
dialog.  In fact, I think they may be better off in a dialog of their
own (something I swore not to do earlier, but oh well).

As I still need to add resolution support to the dialog, it has simply
grown too crowded, and separate "Basic / Advanced" panels were too
unintuitive and ugly.

I will revisit advanced options in the future, but for now, my goal is
to make this core resize dialog as minimalist as possible.  As I have
some interest in hqx and other pixel-art style resize algorithms
(http://en.wikipedia.org/wiki/Image_resampling#Pixel_art_scaling_algorithms),
what I may do is add an "Advanced Resize" submenu to the Image menu, and
move content-aware resize, pixel art resize, and the advanced resize
options there.  (The new SmartResize user control will make it extremely
easy to add new resize dialogs, so yay for one victory today!)