Feature/abortable fetch (#83)

Feature/abortable fetch

Author: niftylettuce

README.md

@@ -211,6 +211,10 @@ const Frisbee = require('frisbee');
 
   * `raw` - return a raw fetch response (new as of v2.0.4+)
 
+  * `abortToken` - some Symbol that you can use to abort one or more frisbee requests
+
+  * `signal` - an [AbortController](https://developer.mozilla.org/en-US/docs/Web/API/AbortController) Signal used to cancel a fetch request
+
 Upon being invoked, `Frisbee` returns an object with the following chainable methods:
 
 * `api.auth(creds)` - helper function that sets BasicAuth headers, and it accepts `user` and `pass` arguments
@@ -223,6 +227,10 @@ Upon being invoked, `Frisbee` returns an object with the following chainable met
 
 * `api.jwt(token)` - helper function that sets a JWT Bearer header. It accepts the `jwt_token` as a single string argument.  If you simply invoke the function `null` as the argument for your token, it will remove JWT headers.
 
+* `api.abort(token)` - aborts all current/queued requests that were created using `token`
+
+* `api.abortAll()` - aborts all current/queued - i.e. `await`-ing in an interceptor - requests
+
 * All exposed HTTP methods return a Promise, and they require a `path` string, and accept an optional `options` object:
 
   * Accepted method arguments:

package.json

@@ -38,6 +38,8 @@
     "Kyle Kirbatski <kkirbatski@gmrmarketing.com>"
   ],
   "dependencies": {
+    "@babel/runtime": "^7.3.1",
+    "abortcontroller-polyfill": "^1.2.4",
     "caseless": "^0.12.0",
     "common-tags": "^1.8.0",
     "cross-fetch": "^3.0.2",