message: document auth provider methods
diff: @@ -3,6 +3,12 @@ import { decodeToken } from 'jsontokens'
  import { updateQueryStringParameter } from '../index'
  import { BLOCKSTACK_HANDLER } from '../utils'
  +/**
  + * Retrieves the authentication request from the query string
  + * @return {String|null} the authentication request or `null` if
  + * the query string parameter `authRequest` is not found
  + * @private
  + */
  export function getAuthRequestFromURL() {
  const queryDict = queryString.parse(location.search)
  if (queryDict.authRequest !== null && queryDict.authRequest !== undefined) {
  @@ -12,6 +18,15 @@ export function getAuthRequestFromURL() {
  }
  }
  +/**
  + * Fetches the contents of the manifest file specified in the authentication request
  + *
  + * @param {String} authRequest encoded and signed authentication request
  + * @return {Promise<Object|String>} Returns a `Promise` that resolves to the JSON
  + * object manifest file unless there's an error in which case rejects with an error
  + * message.
  + * @private
  + */
  export function fetchAppManifest(authRequest) {
  return new Promise((resolve, reject) => {
  if (!authRequest) {
  @@ -38,6 +53,17 @@ export function fetchAppManifest(authRequest) {
  })
  }
  +/**
  + * Redirect the user's browser to the app using the `redirect_uri`
  + * specified in the authentication request, passing the authentication
  + * response token as a query parameter.
  + *
  + * @param {String} authRequest encoded and signed authentication request token
  + * @param {String} authResponse encoded and signed authentication response token
  + * @return {undefined}
  + * @throws {Error} if there is no redirect uri
  + * @private
  + */
  export function redirectUserToApp(authRequest, authResponse) {
  const payload = decodeToken(authRequest).payload
  let redirectURI = payload.redirect_uri
  