Added help options to PDB

Lib/pdb.py

@@ -1238,7 +1238,7 @@ def help():
         print 'along the Python search path'
 
 def main():
-    if not sys.argv[1:]:
+    if not sys.argv[1:] or sys.argv[1] in ("--help", "-h"):
         print "usage: pdb.py scriptfile [arg] ..."
         sys.exit(2)