Allow individual line descriptions on alias bulk import

This enhancement allows the user to make a text file of IP addresses, IP subnets and/or IP ranges, like they have always been able to do, but with this they can put a description after each IP number and that description text will be saved in the alias. All existing functionality without specifying a description is unchanged, so it is backward-compatible.
This is handy when having aliases that are on all my pfSense boxes, I can make 1 text file, bulk import it on every system and now include descriptions of each chunk of IP address space.
See the attached screenshots. What do you think?

![bulkimportinput](https://f.cloud.github.com/assets/1535615/1821603/8055bb98-7139-11e3-9804-5dfd18345f7a.png)
![bulkimportresult](https://f.cloud.github.com/assets/1535615/1821606/8fc7a758-7139-11e3-972d-db5ea0a3a016.png)