[1/2] Base: Clock tweaks

PS5: changed to slim as base for commit:
- Clock and date enable/disable
- Clock and date position
- AM/PM styles multilang support
- color
- Date format
- Date style

PS6:
- Fixed build
- Removed color options because we don't have it for any other
statusbar objects.

PS7:
- fixed clock on lockscreen after reboot
- fixed clock transition
- cleanup

OmniGears: https://gerrit.omnirom.org/#/c/4939/

Change-Id: I9129067775d65119d27085f93efb798a7124ae2c