Disable jmxremote

This commit removes jmxremote which previously could have allowed anybody with access to the machine to load any class that they wished.  Resolves https://github.com/opscode/opscode-omnibus/issues/648.  Users can re-enable via `chef-server.rb` configuration change:

```ruby
opscode_solr4['java_opts'] = '-Dcom.sun.management.jmxremote -Dcom.sun.management.jmxremote.port=8086 -Dcom.sun.management.jmxremote.authenticate=false -Dcom.sun.management.jmxremote.ssl=false'
```