Updated CHANGES.rst.
Added three new template variable operators: .upper(), .lower(), and .uniquify(arg).

The code supporting the ".uniquify()" operator is still under progress.
Updated test1 in testing suite.

This update both tests the new operators .upper() and .lower() and also adds a test for using an explicit index to an implicitly-indexed variable, without a implicit loop present. This wasn't working properly until now.
Modified 'make_sortkey_unique()' in bibulous.py to work correctly with '.uniquify()' operator.