This change makes the setup-repo command easier to follow and understand

by adding more information concerning the purpose of the command, how to

configure repositories, and the overall status of the config file

creation process. 
The repository selection process has been simplified;

multiple repositories can be seen at once, and the repository of choice

can simply be selected without having to go through other repositories.
Unit tests have also been added for the setup-repo command to ensure

functionality in future releases.
I have detailed notes on my current changes here.

Test cases run on python 2.7.17 and 3.7.6:

- Test case validating repository prompt if repositories exist

- Test case validating repository prompt if no repositories exist

- Test case validating config file generation

- Test case validating the contents of config file

- Test case validating server options

- Test case validating perforce options

- Test case validating tfs options