Implemented a convenience function that closes the currently-active project (closes #11).
Implemented interface for GetProjects() (closes #12) and added a corresponding example.
Corrected an error where most of the examples wouldn't run because of a missing argument to the new_project() function (closes #34).
Implemented a convenience function for CloseProject() that closes all open projects (closes #14).  Included a relevant example.
Implemented a convenience function to CloseProject() that closes all open projects except for the currently-active project (closes #15).  Also implemented an example.
Implemented a preliminary version of InsertFrequencySweep() that works for Discrete sweeps of the LinearStep variety (closes #16).  Also implemented a corresponding example.