hammerhead: Add OmniTorch Overlay

PatchSet2: Add values to init.hammerhead.rc (referenced CM)

Change-Id: I1c9db344a879c37a695bb3a3d5eab6772f9beb3d
OmniTorch for Nexus 5 (hammerhead)

Refs from CM

Patchset 3: - add some more information to the overlay
            - put the call in device.mk back to where it was originally
Patchset 4: fix spacing
Patchset 5: Change permission of sysfs parameter

Change-Id: I07f6be272d57d228f2ca32804cf52c4e770e7abd
hammerhead: Clean up Torch

Two squashed commits

hammerhead: Remove global-read/write for torch sysfs

This is a security issue - anything can turn on the LED right now

This is not the proper way to fix torch.

hammerhead: Make OmniTorch use camera interface

Even if you solve permissions issues with sysfs, Torch causes
the camera to be unable to control the flash if you use Torch
then switch to camera when using sysfs.

This has been reported by multiple users of both Omni and CM.

When using the camera interface, Torch works without permissions
hacks and does not interfere with normal camera operation.

Change-Id: I4eb005cb7fce6908a4cfb5fbc7b3e575bd6ab308