Added BroadcastReceiver to change preferences by intents

Just created a simple SettingsReceiver to receive intents broadcasted out from third party apps like Tasker. I just found out that a Tasker plugin is being developed but anyways since I created it I thought I would share.

**Usage:**
_adb shell am broadcast -a com.lr.keyguarddisabler.action.SET_PREFERENCE -e lockscreentype device/slide/none_

Tasker or any other 3rd party app can use Send Intents to send the desired lock screen type and this will take effect on the next screen lock.