Problem: '.-' no allowed in highlight group names
Solution: Allow dot and hyphen characters in highlight group names
Allow dots and hyphens in group names. There does not seem
to be any reason for these to be disallowed.
closes: #12807
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Gregory Anders <greg@gpanders.com>
Co-authored-by: Sean Dewar <seandewar@users.noreply.github.com>
d4376dc3eb
