Add xkb_keysym_from_name() flags argument for case-insensitive search This adds a flags argument to xkb_keysym_from_name() so we can perform a case-insensitive search. This should really be supported as many keysyms have really weird capitalization-rules. However, as this may produce conflicts, users must be warned to only use this for fallback paths or error-recovery. This is also the reason why the internal XKB parsers still use the case-sensitive search. This also adds some test-cases so the expected results are really produced. The binary-size does _not_ change with this patch. However, case-sensitive search may be slightly slower with this patch. But this is barely measurable. [ran: use bool instead of int for icase, add a recommendation to the doc, and test a couple "thorny" cases.] Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>