Rename NetworkStack package

Set the new name to com.android.networkstack. Also rename the stub APK
to com.android.networkstack.permissionstub.

Also add shared UID to the NetworkStackPermissionStub to enforce
signature restrictions on the UID.

Test: booted, WiFi working
Bug: 124033493
Change-Id: Id8967db08b7faaa659b20f86f1013493eb0e188f
3 files changed