Update Markdown FunctionList to allow spaces before header lines

Author: pryrt

functionList/udl_markdown.xml

@@ -11,7 +11,7 @@
         <parser displayName="Markdown (preinstalled)"
                 id="Markdown (preinstalled)"
                 commentExpr="">
-            <function mainExpr="(?x-s)(^[#]+\s*(.*?)$|^(.*)(?=[\r\n]+^([-=])\4{2,}\s*$))"/>
+            <function mainExpr="(?x-s)(^\h*\K[#]+\h*(.*?)$|^(.*)(?=[\r\n]+^([-=])\4{2,}\h*$))"/>
         </parser>
     </functionList>
 </NotepadPlus>