Update codeit.js

Author: benhatsor

lib/codeit.js

@@ -622,7 +622,7 @@ class CodeitElement extends HTMLElement {
             if (selContents.includes('\n')) {
 
               // tab lines in selection
-              selContents = selContents.split('\n').join('\n' + cd.options.tab);
+              selContents = cd.options.tab + selContents.split('\n').join('\n' + cd.options.tab);
 
               // insert tabbed selection
               cd.deleteCurrentSelection();