Linux update notifications

Fixes #257

renderer/views/update-available-modal.js

@@ -0,0 +1,36 @@
+module.exports = UpdateAvailableModal
+
+var h = require('virtual-dom/h')
+var hyperx = require('hyperx')
+var hx = hyperx(h)
+
+var electron = require('electron')
+
+var {dispatch} = require('../lib/dispatcher')
+
+function UpdateAvailableModal (state) {
+  return hx`
+    <div class='update-available-modal'>
+      <p><strong>A new version of WebTorrent is available: v${state.modal.version}</strong></p>
+      <p>We have an auto-updater for Windows and Mac, but not yet for Linux, so you'll have to download it manually. Sorry.</p>
+      <p>
+        <button class='primary' onclick=${handleOK}>Show Download Page</button>
+        <button class='cancel' onclick=${handleCancel}>Skip This Release</button>
+      </p>
+    </div>
+  `
+}
+
+function handleKeyPress (e) {
+  if (e.which === 13) handleOK() /* hit Enter to submit */
+}
+
+function handleOK () {
+  electron.shell.openExternal('https://github.com/feross/webtorrent-desktop/releases')
+  dispatch('exitModal')
+}
+
+function handleCancel () {
+  dispatch('skipVersion', state.modal.version)
+  dispatch('exitModal')
+}