Lockscreen: See through (2/2)
Add the ability to see through lockscreen.
Adapted to kitkat from jellybean by @BigBrother1984

Signed-off-by: D4rKn3sSyS <jesdga95@gmail.com>
Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

PS2:

* Indenting and fix of the LOCKSCREEN_SEE_THROUGH variable check.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

PS3:

* Add see through checkbox to security_settings_chooser.xml, reflects the security_settings_lockscreen.xml.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

PS4:

* Made the option available with every lock mode (PIN, Password etc.) cause it works with every mode now.
* Update description with better one.

Signed-off-by: Carlo Savignano <stevewatersy@gmail.com>

PS5:

* Make description more like aosp strings.

Fix: Ensure lockscreen see through setting persists after reboot
If see through was enabled and the device was rebooted,
the user had to toggle the setting off and on again to activate.