refactor: add js-libp2p-switch to the libp2p codebase (#388)

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test/switch/browser.js

@@ -0,0 +1,12 @@
+/* eslint-env mocha */
+'use strict'
+
+const w = require('webrtcsupport')
+
+require('./transports.browser.js')
+require('./swarm-muxing+websockets.browser')
+
+if (w.support) {
+  require('./t-webrtc-star.browser')
+  require('./swarm-muxing+webrtc-star.browser')
+}