Make allocating IPs a bit easier on the eyes.

This removes the Free IPs section of the network page. This also turns
the static text display for an IP, into an form input to allow
allocating arbitrary IPs.
Add paging support for networks
Order networks/ips by address
Create basic CRUD for IP addresses
Only display network actions if the user is admin
Merge pull request #34 from optopus/feature/network-improvements

Make the network section more useful