GUI: Select tag Enter key behavior

[e3rd]

By default, enter submits the form.

But when a select tag form is focused and the focus is above an item that is not selected, make it the first enter select the item and the second submit the form.

Example. Running the code will raise a window.

$ mininterface select one two three

1. Hit Enter. 'one' gets selected
2. Hit Enter again, the form is submitted.

Here is the SelectTag handler:

mininterface/mininterface/_tk_interface/utils.py

Line 197 in a9c4c70

wrapper = SelectInputWrapper(master, tag, grid_info, widget, adaptor, len(fform) == 1)