Correct .gitmodules file

.gitmodules

@@ -1,3 +1,3 @@
-[submodule "python/dateregex"]
+[submodule "syntax/python/dateregex"]
 	path = syntax/python/dateregex
 	url = https://github.com/victal/dateregex.git

syntax/python/todo.py

@@ -0,0 +1,25 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+import vim
+import os
+import sys
+from datetime import date
+
+dateregex_dir = os.path.join(vim.eval('s:script_dir'), 'dateregex')
+if os.path.isdir(dateregex_dir):
+    sys.path.insert(0, dateregex_dir)
+
+def add_due_date_syntax_highlight():
+    try: 
+        from dateregex import regex_date_before
+    except ImportError:
+        print("dateregex module not found. Overdue dates won't be highlighted")
+        return 
+
+    regex = regex_date_before(date.today())
+    regex = r'(^|<)due:%s(>|$)' % regex
+
+    vim.command("syntax match OverDueDate '\\v%s'" % regex)
+    vim.command("highlight  default  link  OverDueDate       Error")
+
+add_due_date_syntax_highlight()