Show unicode characters by default for arrows keys instead of icons

Previous versions of ASK used Unicode arrow characters for arrow keys by default. I think they're much more cute than current gingerbread-like rounded icons. And the main problem is that now no theme can return to the old look and use characters again, because the code takes that icons as a default!
The issue was previously here: http://code.google.com/p/softkeyboard/issues/detail?id=984
Now I've rebased it against your new version.
Also it changes fallbackIconSetStyleId from fallbackTheme.getIconsThemeResId() (which is the default theme id) to just hardcoded R.style.AnyKeyboardBaseKeyIconTheme.
I assume it's more correct because in theory any theme may be selected as default, and for example if you'll select gingerbread one, with previous code you'll again lose the ability to return back to unicode arrows.

So please review and merge this change! :-)