Made it easier to access FormatDate.* with autocompletion

Rather than use date.format("MNS"), you can now use date.monthNameShort()

To do this, I have moved Dates.format() to Dates.formatOld() (might obsolete it?)
and I have typedef aliased FormatDate into the bottom of the Dates file.

This means all the FormatDate static methods are now available when "using Dates;"
is used.  So you can do

    date.monthName();
    date.universal();
    date.weekDayNameShort();

etc.