JIODate now has 2 methods to switch between local and UTC modes:
localMode() and utcMode(). These were added because JIODate also
exposes methods that can be affected my messing with the moment’s mode
and the user can not be aware of this.

JIODate constructor also now takes into account a second parameter when
parsing date-only strings (i.e., 2016-02-01) to create the moment
object in local or UTC mode. This allows tests that use date-only
strings to be timezone agnostic by using the UTC mode parsing.