Enable readwrite support for lrzipped tar archives in libarchiveplugin.
Libarchive currently uses the lrzip executable to handle this
compression type, so we remove the archive type from filter list in
"Open Archive" and "New Archive" dialogs if the executable is not found
in path.

BUG: 356253
FIXED-IN: 16.04.0
FEATURE:
Differential Revision: D1132