Improve shell and m4 syntax

Julien LepillerMon Jun 28 03:19:08+0300 2021

1b603dc

gitile/assets/css
namelast commitdate
gitile.cssAdjust markdown renderingMon Jun 21 00:50:01+0300 2021
highlight.cssSupport shell and autoconf highlightingMon Jun 28 02:52:43+0300 2021