def merge!(hash)
      hash.each do |key, value|
        if config_contexts.key?(key)
          # Grab the config context and let internal_get cache it if so desired
          config_contexts[key].restore(value)
        else
          configuration[key] = value
        end
      end
      self
    end
def merge!(hash)
      hash.each do |key, value|
        if config_contexts.key?(key)
          # Grab the config context and let internal_get cache it if so desired
          config_contexts[key].restore(value)
        else
          configuration[key] = value
        end
      end
      self
    end
Merge an incoming hash with our config options

 === Parameters
 hash<Hash>: a hash in the same format as output by save.

 === Returns
 self