code: public static boolean sendUpdateMessage(String site2, String repo, String branch, String revision, String comment, String token, String endpoint) throws Exception {
      return sendUpdateMessage(site2, repo, branch, revision, comment, token, endpoint, UpdateRequest.CONTENT_BRANCH_PREFIX);
    }
docs: Sends a update message to a Cadmium site. This method will block until the update is complete.
  
  @param site2 The uri to a Cadmium site.
  @param repo The git repository to tell the site to change to.
  @param branch The branch to switch to.
  @param revision The revision to reset to.
  @param comment The message to record with this event in the history on the Cadmium site.
  @param token The Github API token to authenticate with.
  @param endpoint The endpoint to send the update request to.
  @return true if successfull or false otherwise.
  @throws Exception