Schemas/Readme: more details for each type of configuration file
Schemas/Readme: more details for each type of configuration file

The scope of this readme is widened to document the hierarchy of configuration
files and details on the content of each of them.

Change-Id: I962e0c329dca8f798827ea2e0ba3ec5a9352ee53
Signed-off-by: David Wagner <60228a510f9a76940848fa2d29321fc4edfc2119@intel.com>

android-ia/hardware_intel_parameter-framework,android-ia/hardware_intel_parameter-framework,android-ia/hardware_intel_parameter-framework