isValidTime: check if a time is valid in 24h clock
Description
allow leading and trailing space, optional colon in middle, 2400
is not allowed. TODO: can lubridate do this better?
Usage
isValidTime(tms, na.rm = FALSE)
Arguments
tms
is a vector of characters which may represent times
na.rm
logical if true, will ignore NA values, otherwise these will
test as invalid.
Value
logical vector, with NA out if NA given