static: Add support for building a broken ppc binary
search: Swap ',' and '.' keys + minor refactoring

To be consistent with ncmpc, the , key is next and the . key previous.

I've replaced the function LUTs with just a ternary operator, since the
functions were only being used once and this is much shorter.
(Performance might be slightly worse, but I highly doubt it's
significant)

I've replaced the SEARCH_NEXT/SEARCH_PREV definitions with just a
boolean. Again, shorter, but also clearer when not used as an array
index.

The definition of the REGEX_ things shouldn't be in #if INTERFACE,
they're local in ui_util.c.
search: Start searching from selected item instead of from top

Certainly vim and vifm start searching from the cursor rather than the
start of the file/listing. I'd expect most other applications to do the
same.
search: Wrap to beginning/end on next/prev
search: Fix various memory management issues

ui_listing_search() used to free ul->search, but didn't always set it.
This resulted in double free errors and invalid memory accesses in
ui_listing_search_advance().

ui_listing_search() now always ensures that ul->query points to
something sane.
search: Fix crash when searching an empty list

Broken in 7a8c5d0f6758a4cd38b828f9dabc23de77d5b72b
search: add documentation for key bindings