relax SVN archive

Wrote 2 unit tests for the arguments of the n_state_model.set_domain() user function.

Changed all instances of the 'print_flag' arg to 'verbosity' in the prompt for tab_completion.

Wrote the empty N-state model base class for the unit tests.

Changed 1 instance of the 'print_flag' arg to 'verbosity' in the calculate() function for consistency testing.

Added the framework for the user function arg unit tests of the N-state model.

Wrote the interface of the n_state_model.set_domain() user function.

The specific_fns.n_state_model module is now imported.

Modified the 5-state system test.

The SVD and matrix angles user functions have been shifted back to the align_tensor user function
base class. To compensate, the 'tensors' arg has been added so that a select set of tensors can be
operated on.

Added the n_state_model user function class. No functions are implemented yet.

Yet another design change for the N-state model (as coded in the 5-state system test)!