Added LruCache, which is dependent on android-support-v4.jar.

Added LruCache, which is dependent on android-support-v4.jar. 

Modified onScreenTapped: the formula there now depends on if the picture is larger than the screen or not. This actually needs investigation. I've tested it on a Nexus 7 emulator and it worked there, but I'm not sure about devices with different DPI / screen size.

Modified setImageResource() so it would take into account inSampleSize. But the decision mechanism for what inSampleSize to use (default is 1, i.e. no changed to the original image) is still to implement.