Vite + TypeScript (#836)

Resolves #803

This is an initial commit to allow migrating to typescript bit by bit.
It introduces vite.
It removes all the webpack configuration (which I have no clue what all
the profiling are needed for, and couldn't find anything in the readme).
It also changes a single file from javascript to typescript:
`urlopen.js` -> `urlopen.ts`
Which was done manually, later on I'll see if I can automate most of the
migration.
For now, everything seems to work as expected.
I also upgrades storybook to use vite and renames the stories to jsx (I
honestly don't know why this complexity is needed here, but I'll keep it
for now).

cc: @damianstasik

src/libs/urlopen.ts

@@ -0,0 +1,31 @@
+// @ts-ignore
+import style from './style'
+
+export function initialStyleUrl() {
+  const initialUrl = new URL(window.location.href);
+  return initialUrl.searchParams.get('style');
+}
+
+export function loadStyleUrl(styleUrl: string, cb: (...args: any[]) => void) {
+  console.log('Loading style', styleUrl)
+  fetch(styleUrl, {
+    mode: 'cors',
+    credentials: "same-origin"
+  })
+  .then(function(response) {
+    return response.json();
+  })
+  .then(function(body) {
+    cb(style.ensureStyleValidity(body))
+  })
+  .catch(function() {
+    console.warn('Could not fetch default style', styleUrl)
+    cb(style.emptyStyle)
+  })
+}
+
+export function removeStyleQuerystring() {
+  const initialUrl = new URL(window.location.href);
+  initialUrl.searchParams.delete('style');
+  window.history.replaceState({}, document.title, initialUrl.toString())
+}