Single dot in pagespec translates to 'current page'

IkiWiki.pm

@@ -2401,6 +2401,9 @@ package IkiWiki::PageSpec;
 sub derel ($$) {
 	my $path=shift;
 	my $from=shift;
+	if ($path eq '.') {
+		$path = $from;
+	}
 
 	if ($path =~ m!^\./!) {
 		$from=~s#/?[^/]+$## if defined $from;

doc/ikiwiki/pagespec.mdwn

@@ -78,3 +78,7 @@ filenames of the pages in the wiki, so a pagespec "foo" used on page
 "a/b" will not match a page named "a/foo" or "a/b/foo". To match
 relative to the directory of the page containing the pagespec, you can
 use "./". For example, "./foo" on page "a/b" matches page "a/foo".
+
+If you want to use the name of the page the pagespec is used in, you can use
+a single dot. For example, `link(.)` matches all the pages linking to the
+current page.