code: function loadPolicy(documentPath, name) {
    return plugin.myrmex.fire('beforePolicyLoad', documentPath, name)
    .spread((documentPath, name) => {
      // Because we use require() to get the document, it could either be a JSON file
      // or the content exported by a node module
      // But because require() caches the content it loads, we clone the result to avoid bugs
      // if the function is called twice
      const document = _.cloneDeep(require(documentPath));
      const Policy = require('./policy');
      const policy = new Policy(document, name);
  
      // This event allows to inject code to alter the Lambda configuration
      return plugin.myrmex.fire('afterPolicyLoad', policy);
    })
    .spread((policy) => {
      return Promise.resolve(policy);
    });
  }
docs: Load a policy
  @param {string} documentPath - path to the document file
  @param {string} name - the policy name
  @returns {Promise<Policy>} - the promise of a policy