Restructure clc_public_ip

[bjfelton]

This pull request represents a breaking change to the existing clc_public_ip module.

Now that we've got that out of the way, let me explain what this pull request seeks to accomplish.

1. Restructures module to follow idiomatic, single-resource design (read: it only works on a single server)
2. Adds support for mapping public ip to existing private ip
3. Adds support for specifying port range
4. Addresses issue clc_publicip module Should Support Mixed Protocol Ports #19 by collapsing previous protocol and ports attributes into a single list of dictionaries (ports) that includes protocol (optional, default 'TCP', valid values ['TCP','UDP']), port (required), and port_to (optional) options
5. Removes 'ICMP' protocol since a) it is always enabled and b) providing it without a port to the python-sdk induces an error
6. Adds full test coverage for new code and additional coverage for existing code
7. Updates all related docs and examples

NOTES:

• I have only tested this on a VM's primary network -- more testing should be done when the secondary NIC functionality is finished
• I have confirmed that multiple public ips can be created as long as a private ip is provided on the second (both?) request(s). I did not adjust the docs stating that only a single public ip was possible.

[bjfelton]

I'm going to be adding functionality to this in the next day or two to automatically enable ICMP. It turns out that this is not automatically enabled, so I'm planning to enable the option automatically, as per the current Control experience.

[jwcolbert]

Closing, please submit this PR against the develop_2.0 branch.