Revamping menu and display structure
added thrown exception to construct_past_participle
added function to create past participles
revamped to tests to pass in a function depending on whether a full
inflection or just stem and verb endings are being tested. Skipping all
tests involving output to screen or cloze format pending restructuring
of all output.
revisions to tense names, total revamping of output for create_inflection due to addition of subjunctive and compound tenses