UC: introduce gson and disklrucache

rewrite UpdateCheckService to use Volley with a GsonRequest

add Disklruimagecache and imagecachemanager for future use

Change-Id: Id9d6e2c84778edded80d19f8b2af7609818ff8bc
version: 0.1.7

Change-Id: I7b52ef4806efa93d2d12337578db5e9697dd18c7