updates to qs/readme

[rebmullin]

hey @scottnath - I had a little trouble removing the default all together. It seems that empty githubrepo (from config.yml) value would cause issues when it was being called later down the config.yml (here: ghPagesPrefix: '/{{ githubrepo }}') So for now I left this with the default and just updated the default value. Hopefully with the additional readme instructions this would be more clear..

let me know what you think. If you still see this as an issue i can def circle back to it.

[scottnath]

@rebmullin this is great. Just the little changes above and it's good to go.

thank you for doing this

[rebmullin]

@scottnath - ready for re-review. thanks!

[scottnath]

@rebmullin excellent! merging

thank you