Change localhost to 127.0.0.1

[StevenLooman]

Change localhost to 127.0.0.1.

Fixes #38.

[StevenLooman]

I was planning to add a cli_host parameter, but this also requires changing the storing of sessions. Also, one would also be able to use set cli_host for one session localhost and another session 127.0.0.1. These are the same, but will most likely not be detected as a duplicate.

Therefore, I simply changed localhost to 127.0.0.1.