ConversionUtilsTest: tweak javadoc style
ClassUtils: remove unused import
ClassUtils: clean up style
ConversionUtils: improve javadoc and comments
ConversionUtils: clean up style
ConversionUtils: eliminate raw type usage
WIP: ConversionUtilsTest: test subclass of collection
ConversionUtils: remove unnecessary elses
ConversionUtils: simplify array logic
ConversionUtils: use simpler test
ConversionUtils: be consistent with comment style