build: replace master with main (#36)

* Replace master with main

* Replace 3Amaster with 3Amain (no matches)

Co-authored-by: rename-master-branch[bot] <67068259+rename-master-branch[bot]@users.noreply.github.com>

README.md

@@ -3,7 +3,7 @@ The appCache Nanny
 
 > Teaches the applicationCache douchebag some manners!
 
-[![Build Status](https://travis-ci.org/gr2m/appcache-nanny.svg?branch=master)](https://travis-ci.org/gr2m/appcache-nanny)
+[![Build Status](https://travis-ci.org/gr2m/appcache-nanny.svg?branch=main)](https://travis-ci.org/gr2m/appcache-nanny)
 [![Dependency Status](https://david-dm.org/gr2m/appcache-nanny.svg)](https://david-dm.org/gr2m/appcache-nanny)
 [![devDependency Status](https://david-dm.org/gr2m/appcache-nanny/dev-status.svg)](https://david-dm.org/gr2m/appcache-nanny#info=devDependencies)
 
@@ -93,7 +93,7 @@ or a prompt asking the user to reload the page. And it works very well so far.
 Demo
 ----
 
-![appCacheNanny demo screencast](https://raw.github.com/gr2m/appcache-nanny/master/demo/demo.gif)
+![appCacheNanny demo screencast](https://raw.github.com/gr2m/appcache-nanny/main/demo/demo.gif)
 
 The appCache Nanny comes with a simple server for testing. Start it using Node:
 

appcache-nanny.js

@@ -11,7 +11,7 @@
 ;(function (root, factory) {
   var appCache = (typeof applicationCache === 'undefined') ? undefined : applicationCache
 
-  // based on https://github.com/allouis/minivents/blob/master/minivents.js
+  // based on https://github.com/allouis/minivents/blob/main/minivents.js
   function Events () {
     var events = {}
     var api = this