Deprecate `#map` from `CloudIP` to avoid clash with `Enumerable`

[tokengeek]

Due to fog/fog-core#138 there was an error where CloudIP
addresses could not be inspected.

This appeared here as #17

To avoid potential issues in future we should deprecate #map

Short term; we may want to use something like map! to make it immediately
obvious it is not map and that it commits a change immediately.

Medium term; to keep in-line with Fog's CRUD approach (similar to Rails) we
should probably use #target= followed by #save. This means save needs
to be fully implemented and watch for changes to the target.

However longer term we should help define and implement a Fog standard
for IP Addresses that can be moved between resources.

Fog::AWS::Address for instance is their Elastic IP model but it uses #server=
which is semantically wrong when our CloudIPs can use groups and load balancers
as destinations as well.

I don't think this is high priority since the problem was Fog::Formatador being used
outside it's original context (inspecting anything not just collections and assuming
map == Enumerable#map