Restored smaller Doxygen code block padding.

This is a revert of db5b089cee.

docs/extra.less

@@ -319,7 +319,7 @@ div.fragment,pre.fragment {
 	background:hsl(0,0%,95%);
 	border-radius:4px;
 	border:none;
-	padding:2em;
+	padding:1em;
 	overflow:auto;
 	border-left:4px solid hsl(0,0%,80%);
 }