Adding some composite data tests

[scottopell]

This make a few changes:

1. Moves the "is attribute of type XYZ" check inside each attribute class
2. Adds a test case with both a simple compositedata attribute and a nested compositedata attribute (the latter is not supported)
3. Small exception handler cleanup with telemetry bean registration.

I wanted to change the "is attribute of type XYZ" check to use a more dynamic method to avoid having to list all possible subclasses (ref TabularData vs TabularDataSupport).

Unfortunately this is not an easy change due to the fact that TabularDataSupport actually implements Map, so TabularDataSupport was getting picked up as a JmxComplexAttribute vs a JmxTabularAttribute.
Change was attempted in baa60df

[rayz]

lgtm 😃