[1/2] Base: Lockscreen blur

Show the content behind lockscreen, blurred.

Settings: https://gerrit.omnirom.org/#/c/4702/

Change-Id: I0d7ee20d6b415567f0051d716ba0db2e55511e91

[1/2] Base: Lockscreen blur enhancements

Changed base for lockscreen blur to AOSPAL

Thanks to Kyrylo Mikos <kiril.mik.os@gmail.com>
for smooth background change patch

fix http://jira.omnirom.org/browse/OMNI-544

OmniGears: https://gerrit.omnirom.org/#/c/6061/

Change-Id: I9bf0f37b99d2277f1e62c3a108ad51c5e340b711