class Rubocop::Config

def merge(base_hash, derived_hash)

arguments (i.e., cop names), will also be merged.
with the addition that any value that is a hash, and occurs in both
Return an extended merge of two hashes. That is, a normal hash merge, 
def merge(base_hash, derived_hash)
  result = {}
  base_hash.each do |key, value|
    result[key] = if derived_hash.has_key?(key)
                    if value.is_a?(Hash)
                      value.merge(derived_hash[key])
                    else
                      derived_hash[key]
                    end
                  else
                    base_hash[key]
                  end
  end
  derived_hash.each do |key, value|
    result[key] = value unless base_hash.has_key?(key)
  end
  result
end