Add token authentication

[mtalexan]

Basic token authentication is a strong desire from a number of users. There are a few different implementations of it already available and assumedly tested.

One solution replaces the password argument contents with the token and adds a flag to indicate that's what the password argument contains.
Another solution adds some new arguments that will cause some of the others to be ignored when set.

Any solution should document it in the README

[mtalexan]

Implemented in aarcro/master, which has been pushed to master, but needs testing and documentation.