Check stepping-up and -down for datetime-local input fields from renderer.

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".

Function arguments are (value, step, min, max, [keySequence]).
The hour field respects min/max attributes when they have the same date.
PASS stepUp("2013-01-16T17:00", 1, "2013-01-16T15:00", "2013-01-16T17:00") is "2013-01-16T15:00"
PASS stepDown("2013-01-16T15:00", 1, "2013-01-16T15:00", "2013-01-16T17:00") is "2013-01-16T17:00"
PASS stepUp("2013-01-16T17:00", 1, "2013-01-16T15:00", "2013-01-17T17:00") is "2013-01-16T18:00"
PASS stepDown("2013-01-16T17:00", 1, "2013-01-16T17:00", "2013-01-17T20:00") is "2013-01-16T16:00"
The hour field wraps am/pm.
PASS stepUp("2013-01-16T11:00", 1, "2013-01-16T00:00", "2013-01-16T23:59") is "2013-01-16T12:00"
PASS stepUp("2013-01-16T23:00", 1, "2013-01-16T00:00", "2013-01-16T23:59") is "2013-01-16T00:00"
PASS stepDown("2013-01-16T12:00", 1, "2013-01-16T00:00", "2013-01-16T23:59") is "2013-01-16T11:00"
PASS stepDown("2013-01-16T00:00", 1, "2013-01-16T00:00", "2013-01-16T23:59") is "2013-01-16T23:00"


PASS successfullyParsed is true

TEST COMPLETE