Load the checks defined in the specified files.

def LoadChecksFromFiles(file_paths, overwrite_if_exists=True):
  """Load the checks defined in the specified files."""
  loaded = []
  for file_path in file_paths:
    configs = LoadConfigsFromFile(file_path)
    for conf in itervalues(configs):
      check = Check(**conf)
      # Validate will raise if the check doesn't load.
      check.Validate()
      loaded.append(check)
      CheckRegistry.RegisterCheck(
          check,
          source="file:%s" % file_path,
          overwrite_if_exists=overwrite_if_exists)
      logging.debug("Loaded check %s from %s", check.check_id, file_path)
  return loaded