autoviv new repos by user only on "C" access

we've removed the facility of auto-viving "W" access repos when they are
not wildcards.  A wildcard pattern like foo/CREATER was
indistinguishable from a non-wildcard repo, and resolving it was
becoming kludgier and kludgier.  (See the revert in the commit before
this one for details).

As a side effect of not being able to distinguish wildcard repos from
real repos easily, the expand command now works for a normal repo too
(because we have to make it work for "foo/CREATER")

src/gitolite.pm

@@ -179,6 +179,8 @@ sub parse_acl
     return unless $repo;
 
     return $ENV{GL_REPOPATT} = "" if $repos{$repo};
+
+    # didn't find $repo in %repos, so it must be a wildcard-match case
     my @matched = grep { $repo =~ /^$_$/ } sort keys %repos;
     die "$repo has no matches\n" unless @matched;
     die "$repo has multiple matches\n@matched\n" if @matched > 1;