Basic auth (existing instannces: read commit text)

First, chill:
After you pull this, your current installation is supposed to
work fine *as is* (please let me know if it doesn't).

Nevertheless, it is recommended to enable basic auth by adding
these 2 lines to the `[swizzler]` section of `cherrypy.config`
(also documented at `cherrypy.config.example`)

    browser_user: 'someuser'
    browser_password: 'somepassword'

User and password don't need to be too long and funky
(or have anything to do with the user:pasword at rpc_url).
It's just a line of defense against [for example] trojans
who may not have significant file system rights,
but can still TCP-connect to localhost ;)

Existng apps should also `chmod 600 cherrypy.config`
(running `/.install.sh` again will do this as well),
because it would now contain a plaintext password
(and we don't want trojans yada yada).

Swizzle safely.