Basic auth does not handle passwords with colons

[lucap]

Basic auth does not allow for passwords containing one or more colon (:) characters.

For example:

> > > basic_auth, basic_pass = auth_decoded.split(':', 2)
> > > Traceback (most recent call last):
> > >   File "<stdin>", line 1, in <module>
> > > ValueError: too many values to unpack
> > > 
> > > ```
> > > ```

Proposed fix:
```basic_auth, basic_pass = auth_decoded.split(':', 1)