Between the time the user loads the footprint preview in cvpcb or Add
Footprint in pcbnew, we don't need to verify cache integrity to display
the footprint. We use the cache copy when displaying until we close the
selection window and re-open. This limits our need to iterate over the
full directory on every footprint display.
Alternate solutions for v7 should include looking into libfswatch for
change detection
1) make sure we get the default netclass when we want it
2) escape for HTML (particularly important for "<invalid>", but also
for reporting user rule names, netclass names, etc.)
Be more intelligent about sorting lib tree items. (Footprint
entries, for instance, come out of an already-sorted list.)
Don't recreate menus twice when laoding Footprint Editor.
More pervasive use of WX_FILENAME to avoid expensive calls to
wxFileName::SplitPath() and string concatenation.
For POSIX kernels do all the work on the file-system side so we
don't have to keep converting back and forth between encodings.
Jeff Young
Seth Hillbrand