[t] command line option test descriptions now more accurate
Testing --month and --year in command line options
[t] using autodie
[t] Program should barf without command line options
[t] program should generate a TeX file with at least one valid option
Extracted option reading into a subroutine

Using pod2usage() to barf if there aren't any options or if something goes
wrong when GetOptions() runs.
Generating reporting period text in TeX file
Testing that another month value gives expected TeX
Have decided that --month must be specified with --year
Expected --month period text is in the format MM/YYYY
Time period text for only --year now correct
PDF file now correctly built by make