Gui should display nested classes under their containing classes

[Charlie Poole]

Issue is now tracked at https://github.com/nunit/nunit-framework/issues/25 (framework)
and https://github.com/nunit/nunit-gui/issues/7 (gui).

Currently, the Gui displays nested classes entirely separately from the classes that contain them. It would be more natural to display them as children of the enclosing class. When the enclosing class is selected, all nested classes will execute.

If the enclosing class is not itself a test fixture, then there is no further affect.

If the enclosing class is a test fixture, then this will also impact the order of test execution, whether the Gui is used or not. Nested fixtures will execute only after the setup for the enclosing fixture completes. They will not execute if that setup throws an exception. The enclosing class teardown will execute only after all the teardowns for the nested fixture complete. If the enclosing fixture contains test cases in addition to the nested fixture, the order of execution between those cases and the fixture is not defined.

[Mike Gray (mgray88)]

This is exactly what I'm looking for

[Charlie Poole (charlie.poole)]

Moved issue to https://github.com/nunit/nunit-gui/issues/7