allow apps access to the keystore, dhcp/pptp fixes, wifi fixes and isolated_app access

- allow all apps to connect to the keystore over unix socket
- dhcp runs scripts in /system/etc/dhcpcd/dhcpcd-hooks and creates/removes lease files
- mtp connects to dnsproxyd when a pptp vpn connection is established
- allow appdomain to also open qtaguid_proc and release_app to read qtaguid_device
- WifiWatchDog uses packet_socket when wifi comes up
- apps interact with isolated_apps when an app uses an isolated service and uses sockets for that interaction
- for apps with levelFromUid=true to interact with isolated_app, isolated_app must be an mlstrustedsubject

Change-Id: I09ff676267ab588ad4c73f04d8f23dba863c5949
Signed-off-by: Joshua Brindle <jbrindle@tresys.com>
diff --git a/seapp_contexts b/seapp_contexts
index 25d7316..f63da7c 100644
--- a/seapp_contexts
+++ b/seapp_contexts
@@ -41,4 +41,4 @@
 user=_app seinfo=media domain=media_app type=platform_app_data_file
 user=_app seinfo=release domain=release_app type=platform_app_data_file
 user=_app seinfo=release name=com.android.browser domain=browser_app type=platform_app_data_file
-user=_isolated domain=isolated_app levelFromUid=true
+user=_isolated domain=isolated_app