def override(name, val = NULL)
      if null?(val)
        overrides[name.to_sym]
      else
        overrides[name.to_sym] = val
      end
    end
def override(name, val = NULL)
      if null?(val)
        overrides[name.to_sym]
      else
        overrides[name.to_sym] = val
      end
    end
Set or retrieve the overrides hash for one piece of software being
 overridden. Calling it as a setter does not merge hash entries and it will
 set all the overrides for a given software definition.

 @example
   override 'chef', version: '1.2.3'

 @param [Hash] val
   the value to override

 @return [Hash]