use datetime module to calculate times; refactor
convert readme.rst to README.md
add functionality for figuring mileage
add function to figure gross pay and effective hourly rate
finish rewrite of tc.py

the rewrite is intended to make it easier to read and to extend with more
functionality later if desired.
add reg_overtime_hours function to calculate regular hours and overtime hours from weekly hours
add job_hours function to calculate hours per job
add weekly_hours function to calculate weekly hours
add daily_hours function to calculate hours worked each day
add .gitignore, add test_total_hours, restructuring
fix bug in parse_line and change test_parse_line to catch it
add working parse_line function
add readme.md
start rewriting tc as tc.py, add test_tc.py, remove tc.cpp because it's unnecessary
add print out of total regular and overtime hours
improve daily hours figuring
add feature to print out hours for each line