Calculate new repository link from ssh path in configure script

[gazayas]

Closes #1607.

I figured we didn't want to entirely get rid of the ask methods here in case developers decide not to setup their project with GitHub. I tested the configure script against a personal repository of mine so it should work, but you can pull it down with this branch if you want to check it out:

> git clone -b refactor-github-details [email protected]:bullet-train-co/bullet_train.git bt_test