#11 Delete category causes projects to be invisible

[Keith Tyler]

Any projects categorized in a category which is then
deleted are then invisible from the UI.

The correct behaviour should be to move such projects
to "Uncategorized".

Workaround: Access the project via URL hacking to
replace the value of "pid" to that of the lost project,
then use the Manage This Project function to
recategorize the project.