Fix: external storage problem PIE applications + last optimize

If the user binds an app which is located on the
external sdcard and is rebooting the button icon
will be left blank because the PIE is already
constructed before the sdcard is mounted. To avoid
this we listen to the app available intents.
If it is not available it shows the
none graphics. When available it shows the
correct app icon. So that the user can clearly see
this app is accessable or not. As well when the
user goes into mass storage mode or does
unmount the sdcard or whatever case could
happen that the application is not there.

This commit optimize as well the last open things.
BroadcastReceiver as well settingsobserver
are completly turned of when PIE is not in use
as well we destroy the object. I am a friend of
optimizing....think more is not possible and can
be for sure now called to be the resource less
using PIE around.

With this commit I will finally close now project
SlimPIE....all reported issues are done and I want
to begin a new project :p

The application storage problem should be also done
for navbar and navring
which will follow in a sepperat commit

cheers

Change-Id: I814860b9bc843e824e7e36bb521c402b86d24989

Conflicts:
	packages/SystemUI/src/com/android/systemui/statusbar/policy/PieController.java