Cut v2.1.0

The beta release has been proven to work and it's time to release the
public 2.1.0. Knowing how much has changed in this release I expect a
few things to break as a result, and I'll try to address anything as
quickly as I can.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "import-js",
-  "version": "2.1.0-beta.8",
+  "version": "2.1.0",
   "description": "Simplifies importing JavaScript modules",
   "bin": {
     "importjs": "./bin/importjs.js",