Fix [:upper:] and [:lower:] for Unicode characters (bug#11309)

Fix [:upper:] and [:lower:] for Unicode characters (bug#11309)

* src/regex-emacs.c (execute_charset): Add canon_table argument to
allow expression of a correct predicate for [:upper:] and [:lower:].
(mutually_exclusive_p, re_match_2_internal): Pass extra argument.
* test/src/regex-emacs-tests.el (regexp-case-fold, regexp-eszett):
New tests.  Parts of regexp-eszett still fail and are commented out.