Added infrastructure to allow basic member methods in the expressions
language to be called. The methods must have a signature with no arguments. Also
added the following member methods for date fields (and it should be easy to add more)
* getYear
* getMonth
* getDayOfMonth
* getHourOfDay
* getMinutes
* getSeconds
Allow fields to be accessed without using the member variable [value].
(Note that both ways can be used to access fields for back-compat.)
closes#10890