Add utility class with generic type methods

This class recapitulates some of the functions from ConversionUtils
and ClassUtiles, as well as adding new functionality. The previous
methods will be deprecated in favor of those in this class.
Deprecate methods now available in GenericUtils
ClassUtils: tweak javadoc style
ClassUtils: refactor setValue method
ClassUtils#setValue: use more exact field type

Rather than calling field.getGenericType(), let's use the superior
GenericUtils.getFieldType method to get the more exact generic type.
Update unit tests for GenericUtils

This converts the tests of now-deprecated methods from ClassUtils and
ConversionUtils to test the analogous GenericUtils methods instead.