Add request toggles to images config

*Updated images config
-Removed restricted_endpoint toggle
-Added allow_post_images toggle for POST /images
-Added allow_put_image_file for PUT /images/<image_id>/file
-Added allow_get_image_file for GET /images/<image_id>/file
-Added allow_create_update_public_images for public images

Change-Id: I64aed0841ed8bd8ca4b845f03b925f389cbdec3e
Merge "Add request toggles to images config"