Merge branch 'cleanup-license' into 'master'

src/libmtime.py

src/libmtime_hl.f90

src/mtime.py

src/mtime_c_bindings.f90

src/mtime_calendar.c

src/mtime_calendar360day.c

src/mtime_calendar365day.c

src/mtime_calendarGregorian.c

src/mtime_constants.f90

src/mtime_date.c

src/mtime_datetime.c

src/mtime_error_handling.f90

src/mtime_eventHandling.c

src/mtime_eventList.c

src/mtime_iso8601.c

src/mtime_iso8601.rl

src/mtime_julianDay.c

src/mtime_t_datetime.inc

src/mtime_t_event.inc

src/mtime_t_juliandelta.inc