Arbitrary resource types - added json/xml recognition

Added extension based recognition for json and xml resources to the
Default Recognizer. This could be extended to support more common
IANA media types.
Arbitrary resource types - added Metatype Recognizer

Added a recognizer for metatype files by a simple test on Resources
with mimetype xml.
Arbitrary resource types - added tests

Extended existing test suite with recognition of json & metatype
files. The former also specifies the version as part of the
filename. The latter does not.
Corrected small javadoc incorrectness

The method removes the analyzer