Fixes relative time formatting issue for dates in future

All variations of getRelativeTimeSpanString() now properly handle dates
that are in the future. Prior, the version used by
getRelativeDateTimeString() would occasionally show the time instead of
a date when the future date was the same weekday as the current weekday.
This resulted in the time output being duplicated, eg.: "11:23, 11:23"

Change-Id: If20972a6942cce792fa233437f94dedfb71379f3
Signed-off-by: Steve Pomeroy <steve@staticfree.info>