type Period: <"description">
    periodMultiplier int (1..1) <"A time period multiplier, e.g. 1, 2 or 3 etc. A negative value can be used when specifying an offset relative to another date, e.g. -2 days.">
    testMany TestType (0..*) <"Test many">
    testSome TestSomeType (1..*) <"Test some">
    testMaybeOne TestZeroOneType (0..1) <"Test zero or one">
    testAll Test (2..15) <"Test all">