parseTime package:text-iso8601
Parse a time of the form HH:MM[:SS[.SSS]].
Parse a time zone.
The accepted formats are Z, +HH, +HHMM, or
+HH:MM. (+ can be -).
Accepts -23:59..23:59 range, i.e. HH < 24 and
MM < 59. (This is consistent with grammar, and with what
Python, Clojure, joda-time do).