Delete not always propogating through relationships

[gavin-black]

In many cases deleting requests only deletes the parent and not the related children. For example if you have a User with many Posts, and delete the user the corresponding posts are not necessarily deleted.

[gavin-black]

Fixed by b8900d5

The Model was not using cascade as a delete rule. Checked delete rule cases by hand, since there was no obvious sane way to programmatically change relationship delete rules for unit tests.