Returns a boolean describing whether an event is offical, using TBA's event type code.
Examples
is_event_official(read_event("2016parr"))
#> Error in is_event_official(read_event("2016parr")): could not find function "is_event_official"
is_event_official(read_event("2016pahat"))
#> Error in is_event_official(read_event("2016pahat")): could not find function "is_event_official"