* Implement IDeliveryCacheProgressService in bcat
This stub IDeliveryCacheProgressService IPC interface as we don't plan
to support cache delivery.
* Address jd's comments
* Address jd's comment correctly
* Address gdk's comments
* Refactoring HOS folder structure
Refactoring HOS folder structure:
- Added some subfolders when needed (Following structure decided in private).
- Added some `Types` folders when needed.
- Little cleanup here and there.
- Add services placeholders for every HOS services (close#766 and #753).
* Remove Types namespaces