[zaphod-v0.3]: [bug] Typo in port forwarding rule.

SYNOPSIS
[modified]m42/zaphod.py: Incorrect rule name in port forwarding rule.

DETAILS
Some quoting characters were getting into the rule name. There was
no need to add double quotes to the rule string.
[zaphod-v0.3]: [bug] Forgot to dummy out ifaddresses_function in some tests.

SYNOPSIS
[modified]m42/test/test_iputil.py: Dummied out ifaddresses functions in 2 tests.

DETAILS
pingallsubnets uses the ifaddresses_function which needs to be dummied
out for testing. Also since mac2ip call pingallsubnets, the
ifaddresses_function needs to be dummied out to test it as well.
[zaphod-v0.3]: Update READM with install instructions for fping.

SYNOPSIS
[modified]README: Install instructions fping and better Mac Ports instructions.
[zaphod-v0.3]: Raise an exception if the IP address cannot be inferred.

SYNOPSIS
[modified]m42/zaphod.py: In _login_parameters, raise exception if ip is None.

DETAILS
If the IP address of a VM cannot be inferred raise an exception. This
can happen if the ARP table does not contain the IP address of the
virtual machine. Typically this is because the host hardware doesn't
support bridging. (E.g. trying to bridge to the wireless port
of a Mac OS X machine.)