Add seinfo parsing to PackageManagerService.

This patch set allows the PMS to parse the
mac_permissions.xml file which contains the
seinfo values. Each package that is installed
on the device will be assigned an seinfo value
based on policy. This seinfo value will help label
the app process and data directory. Modifications
also include, adjustments to ApplicationInfo.java
to store the seinfo tag per package, adjustments
to installd to communicate the seinfo tag to
libselinux, and finally a set of unit tests.

Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>

Change-Id: I61ad1ea12fb6a9a6d0b108ec163bc4bf4c954b58
Added SELinux enforcing status and booleans keys to secure system settings.

Conflicts:
	core/java/android/provider/Settings.java

Change-Id: I01f2a9084dfe7886087b1497070b0d7f2ad8474e
Save off the seinfo value with packages.list.

Patch adds the seinfo label per package to the file.

Change-Id: I01f2a9084dfe7886087b1497070b0d7f2ad8475e