Framework : Lockscreen - Customizable shortcuts

Allow users to choose lockscreen shortcuts / icons :
	Phone - 1-5 targets
	Tablets - 1-8 targets

CM10 port
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Patchset 1-8: Initial port
Patchset 9  : Revert to CM9 drawables
Patchset 10 : Rebase

Change-Id: I9b163efeef8f47b1d21f7f61552ebe424049cfeb