SystemUI: Customize StatusBar for China carriers

1. Show carrier label in notification panel.
2. Support monitor locale change and display for radio tech.
3. Update Chinese roaming string.
4. Show wifi activity in status bar.
5. Show indicator for Wifi on but not connected.
6. Show rsrp level for LTE.
7. Redesign the scheme of selecting icons on signal cluster.
   Customized SigalClusterView and MobileSignalController to adapt
   requirement from China carriers. The customization is controller
   by config values defined in overlayed config.xml.
8. Add customized China carriers resoure files

CRs-Fixed: 916021
Change-Id: Id71a0c98f1a65f31d9a81ddba61d78570e7a96ba