Revert Headsup, there is an app now for that :)

This reverts commit e8a3300cd82779015e80625b973d9c738e704cd9.

Revert "Hide heads up settings and show a notice if heads up is disabled."

This reverts commit dc578a7c9601d2994ac1cf42de2c3a0449d57474.

Revert "Remove SystemSettingSwitchPreference"

This reverts commit a05daa8178955c17be5dafa6dcf493dc14e4a820.

Revert "fixes for heads up"

This reverts commit 1dd3582cd1d8ab78b44a824af4cdca11fbf4c7f3.

Revert "Deduplicate adapter-of-installed-packages code."

This reverts commit cb3aafcaa1aef1cd39c413974e2d154c1e2c06e1.

Revert "Settings: Add heads up blacklist options. (2/2)"

This reverts commit d336134d99d54a15e5bb30aa6d485dcabe3004cf.

Revert "Settings: Add HeadsUp setting."

This reverts commit 8d05d7a6bfc75fbec5b9dee99bf0ca868374c7d1.
update string for peek