Fix mistake in Validate\Time class docstring.

Change line describing two digit year number from range 70-99
True information say that:
if year value is in range 70-99, is interpreted as 1970-1999.
Fix mistakes, add test Cases in Validate\Time class.
Add more test cases for Validate\Time class
Add date-time format generator and constructor body
Add test cases
Correct Zend Framework library path in tests bootstrap
Fix bug in getValidator method
Implements Validate\Time class