Android: Rewrite listbox multiple selection... keep track of the selection ourselves using a "multiple" list in our DWListBox class. Show that an item is selected by changing its background to dark gray. I try to do the "native" thing on platforms when possible, but the Android native checked item wasn't really working. Can revisit later if we want a more native version.

# Set these here to change the version for all platforms
DW_MAJOR_VERSION=3
DW_MINOR_VERSION=2