Add HP and Mopria print recommendation service

- Make util.MDnsUtils local to the mdnsFilter plugins
- Remove HP from the vendors recommended via the mdnsFilter plugin
- Copy in HP's code for HP and Mopria plugin
  - Do not change any code, beside
    - change "_ipp.tcp" to "_ipp._tcp"
    - Change package name
    - Do not use support lib annotations
    - Reduce class visibility if possible
    - Add AOSP copyright
    - Make ServiceResolveQueue a proper sigleton
    - Merge donottranslate and strings
- Add HP and Mopria plugin to RecommendationServiceImpl
- I needed to implement a multiplexer for NsdManager.DiscoveryListener
  as we can only have 10 of them active at a time.

Change-Id: I61caa3f4822f9c013140721ed801d18e6839df55