bpo-5680: IDLE: Customize running a module (GH-13763)

The initialize options are 1) add command line options, which are appended to sys.argv as if passed on a real command line, and 2) skip the shell restart. The customization dialog is accessed by a new entry on the Run menu.

Lib/idlelib/idle_test/htest.py

@@ -108,6 +108,15 @@ _color_delegator_spec = {
            "The default color scheme is in idlelib/config-highlight.def"
     }
 
+CustomRun_spec = {
+    'file': 'query',
+    'kwds': {'title': 'Custom Run Args',
+             '_htest': True},
+    'msg': "Enter with <Return> or [Ok].  Print valid entry to Shell\n"
+           "Arguments are parsed into a list\n"
+           "Close dialog with valid entry, <Escape>, [Cancel], [X]"
+    }
+
 ConfigDialog_spec = {
     'file': 'configdialog',
     'kwds': {'title': 'ConfigDialogTest',