Two new types are introduced:
sdcard_internal
sdcard_external

The existing type of sdcard, is dropped and a new attribute
sdcard_type is introduced.

The boolean app_sdcard_rw has also been changed to allow for
controlling untrusted_app domain to use the internal and external
sdcards.

Change-Id: Ic7252a8e1703a43cb496413809d01cc6cacba8f5

Target the denials/policies over qtaguid file and device: 1. Relabel /proc/net/xt_qtaguid/ctrl from "qtaguid" to "qtaguid_proc"; 2. Label /dev/xt_qtaguid with "qtaguid_device"; 3. Allow mediaserver read/[write] to qtaguid_proc and qtaguid_device; 4. Allow media apps read/[write] to qtaguid_proc and qtaguid_device; 5. Allow system read/[write] to qtaguid_proc and qtaguid_device.

Actually, some of policies related to qtaguid have been there already, but
we refind existing ones and add new ones.

ocontexts was split up into 4 files:
1.fs_use
2.genfs_contexts
3.initial_sid_contexts
4.port_contexts

Each file has their respective declerations in them.
Devices, in their respective device directory, can now specify sepolicy.fs_use, sepolicy.genfs_contexts, sepolicy.port_contexts, and sepolicy.initial_sid_contexts. These declerations will be added right behind their respective sepolicy counterparts in the concatenated configuration file.