Problem: Searching for "a" does not match accented "a" with new regexp
engine, does match with old engine. (David Bürgin)
"ca" does not match "ca" with accented "a" with either engine.
Solution: Change the old engine, check for following composing character
also for single-byte patterns.
Problem: Searching for composing char only and using \Z has different
results.
Solution: Make it match the composing char, matching everything is not
useful.
Problem: New regexp engine is inefficient with multi-byte characters.
Solution: Handle a character at a time instead of a byte at a time. Also
make \Z partly work.
Problem: New regexp: adding \Z makes every character match.
Solution: Only apply ireg_icombine for composing characters.
Alsl add missing change from patch 1008. (Ken Takata)
Problem: Test 95 fails on MS-Windows.
Solution: Set 'nomore'. Change \i to \f. Change multi-byte character to
something that is not matching \i. (Ken Takata)
Problem: No easy to run an individual test. Tests 64 fails when
'encoding' is not utf-8.
Solution: Add individual test targets to the Makefile. Move some lines from
test 64 to 95.
Problem: Syntax highlighting can be slow.
Solution: Include the NFA regexp engine. Add the 'regexpengine' option to
select which one is used. (various authors, including Ken Takata,
Andrei Aiordachioaie, Russ Cox, Xiaozhou Liua, Ian Young)
