[Integrated Terminal] Allow ctrl+backspace to delete entire word in cmd.exe

Within the integrated terminal using `cmd.exe`, I'd like to be able to use `ctrl+backspace` in order to delete an entire word, as can be done in the regular editor. `ctrl+backspace` *does* work inside powershell, but not when using `cmd.exe`.

This is currently possible within the new Windows Terminal as well as the "old" Windows 10 terminal,
https://github.com/microsoft/terminal/issues/755
