Revert "Custom wallpaper: use PNG"

This reverts commit 2ca7372e63df8debd3d1a7b8769ba551b0f9441f.

Conflicts:
	src/com/android/settings/AOSPAL/AdditionalSettings.java
Revert "Custom lockscreen wallpaper [2/2]"

This reverts commit 2884f0d7ef4d504a347414db6912ebf2ad94066c.

Conflicts:
	res/values/pa_strings.xml
	res/xml/additional_settings.xml
	src/com/android/settings/AOSPAL/AdditionalSettings.java
	src/com/android/settings/SecuritySettings.java