YAMLish allow blank lines with less indentation

gistfile1.txt

--- a/lib/YAMLish.pm6
+++ b/lib/YAMLish.pm6
@@ -223,7 +223,7 @@ grammar Grammar {
                <.comment>? <.line-break>
                :my $new-indent;
                <?before $indent $<sp>=' '+ { $new-indent = $indent ~ $<sp> }>
-               [ $new-indent $<content>=[ \N* ] | $indent <.before <.line-break> > ]+ % <.line-break>
+               [ $new-indent $<content>=[ \N* ] | ' ' ** { 0 .. $indent.chars } <.before <.line-break> > ]+ % <.line-break>
        }

        token yes {