Add filesystem support under tab completion

[vshesha]

Thank you for this wonderful package. The following is an enhancement request. There are cases where we need to pass in the relative file path under certain commands.

Example:
>>>mycmd file ../../file.txt

A bash style tab support that will validate and autocomplete file path will enhance the user experience.

[bharathshetty4]

+1

I wanted to do a cd type of tab completion, I want not able to do it using the completer.