base: Introduce app lock [1/4]

base: applock: refactor

* encapsulate config data sources and add a data class for per app config
* added support for migrating between different versions of data
* fixed notification content not being redacted.

services: applock: allow background authentication

base: merge hidden app feature with applock

services: AppLockConfig: fix a derp in hidePackage()

services: applock: fix data migration and change secure notification parameter name

* also fixed addPackage replacing data without checking if entry already exists

services: AppLockManagerService: use the og calling uid for target intent

* fixes launching app activites not exported

* nift4: avoid changing public api

* @neobuddy89: Add privapp permissions for Settings, updated for A14

Change-Id: Ie35c6c7103b8bed644d510d8268d6c99cb71a1a2
Signed-off-by: Pranav Vashi <neobuddy89@gmail.com>