Update more terminology in images and markdown documents

Author: padenot

README.md

@@ -1,11 +1,11 @@
 # Web Audio API 1.0 Spec
 
 
-[![Build Status](https://travis-ci.com/WebAudio/web-audio-api.svg?branch=master)](https://travis-ci.com/WebAudio/web-audio-api)
+[![Build Status](https://travis-ci.com/WebAudio/web-audio-api.svg?branch=main)](https://travis-ci.com/WebAudio/web-audio-api)
 
 This repository contains the latest editor's draft of the [W3C AudioWG](https://www.w3.org/2011/audio/)'s Web Audio API v1.0.
 
-You can preview the current version of the master branch [here](https://webaudio.github.com/web-audio-api/).
+You can preview the current version of the `main` branch [here](https://webaudio.github.com/web-audio-api/).
 
 # Tests
 

images/modular-routing2.graffle

@@ -49,7 +49,7 @@ Changes between the 8 December 2015 Working Draft and the 19 June 2018 draft are
 https://webaudio.github.io/web-audio-api/#changestart
 
 More recent changes are listed here
-https://github.com/WebAudio/web-audio-api/commits/master
+https://github.com/WebAudio/web-audio-api/commits/main/
 and will be added to a separate changes subsection
 
 The remainder of Web Audio API is stable, has multiple implementations, and is widely used.