Ability to delete domains

[jonaharagon]

Grant the ability for users to delete domains. Design-wise this can be accomplished by changing the code for the "Save" button in the table from:

<td><a class="btn z-depth-0">Save</a></td>

to

<td><a class="btn z-depth-0">Save</a>&nbsp;&nbsp;<a class="btn z-depth-0 red"><i class="material-icons">delete</i></a></td>

Which will look something like:

Immediately after deletion, the associated record should be deleted, not all records for the domain, for example, they may only want to delete a single NS record (after #3 is completed). If the last record for a domain is deleted the domain can be released back into the available pool. All domains require at least 1 record to be considered registered (to prevent losing your domain, you should add a TXT holding record or similar after #16).