Add a local datasource collector to occ

This spec details adding a local datasource collector to
os-collect-config. The collector will collect configuration data from
well known directories, allowing multiple elements to install and apply
configuration data to an instance in the same image build. This will allow
elements to supply configuration data for runtime consumption.

Change-Id: I221a38dff2064ff0df0628140d80498949c6d16d
Merge "Add a local datasource collector to occ"