Currently for a class used in component property types the property
looks like MyClass.class where according to the spec it should be a
string holding the class name, also empty arrays result in a property
with no value in the xml while the spec says it should be omitted,

This is now fixed, empty properties are only removed and Types are
resolved to their type name from now on.

See also https://github.com/osgi/osgi/issues/646