Status bar: Add customizable date, (1/2)

Based on Slimroms:

https://github.com/SlimRoms/frameworks_base/commit/42bf1be5fbeaab01131bc2c56d879fc7c82fb1f6

Included:

- Enable/disable date
- Custom date color linked to clock color
- fixed am/pm style disappearing on center clock
- Fully customizable date in style and format

Change-Id: Ie1b1fe46e2c5155efa16451f3de03a25410067fb