Add a dependencies feature for composite tests

[Randle Taylor]

For composite tests we may want to add a "dependencies" feature so that tests which are dependent on other tests are automatically included when the composite test is added to a list.

For example, the temperature pressure correction, Ftp, is a Composite Test which depends on air pressure and temperature Tests. When a user defines the Ftp Test, they would add T & P as dependent Tests. Then when they add the Ftp Test to a Test List the T & P Tests would also be added automatically to the Test List.

Pros:
* Reduces the chance that a physicist forgets to add Composite Test dependencies when creating a Test List. * May allow for a more robust validation method for Composite Test calculation procedures

Cons: * This adds a little bit more complexity to the data model * more code