rename the *.json.rz to *ruby - they have no json content and are not deflated ruby objects but just ruby objects.

people already tried to runzip those json.rz files which did not succeed.
Merge pull request #805 from mkristian/rename-json-rz-to-ruby-file

rename the *.json.rz to *.ruby
Merge remote-tracking branch 'origin/nexus-2.11.x' into nexus-2.11.x-more-resource-cleanup

Conflicts:
	plugins/rubygem/nexus-ruby-tools/src/test/java/org/sonatype/nexus/ruby/MetadataBuilderTest.java