Create an interactive process to add mentor

In order to make the process easier, adding a mentor could be done with interactive CLI (command line interface) process. It can be done with prompts for example.

The process should:

1. Collect all the fields by the schema and validate the inputs. ~2. Run yarn run sync-lists.~ https://github.com/Coding-Coach/find-a-mentor/issues/56
2. git add . and git commit -m "add {mentor's name} as mentor"

So the user only need to git push.

To start the wizard, the user will run yarn run add-user (add a scripts in package.json).

The start of the process similar to:

README.md should update accordingly.

[07Gond]

Good, I’m going to start this today.

[emmabostian]

This is so fricken cool.