refactor: remove checks for JS features

Since I'm introducing Svelte framework and targeting modern browsers, I
think it does not make sense to check for browser features. I can always
choose to use polyfills for backwards compatibility.

I will make sure the form is still also rendered via HTML and works for
non-SPA use.

lib/static/index.js

@@ -1,4 +1,4 @@
-import { uuidv4, parseStartTimeFromiCalString, useStorage } from './app/utils'
+import { uuidv4, parseStartTimeFromiCalString } from './app/utils'
 import {
   migrateRecord,
   getStorage,
@@ -16,11 +16,6 @@ import generateICS from '../../lib/services/ics-generator'
 import boot from '../frontend'
 
 (() => {
-  if (!window.fetch || !window.Promise || !window.URLSearchParams || !window.crypto) {
-    console.warn('JS features not available.')
-    return
-  }
-
   document.addEventListener('DOMContentLoaded', boot)
 
   const showTable = () => {
@@ -30,10 +25,6 @@ import boot from '../frontend'
   const deleteTableRow = (id, row) => {
     deleteRecord(id)
 
-    if (!useStorage()) {
-      return
-    }
-
     row.remove()
   }
 
@@ -95,10 +86,6 @@ import boot from '../frontend'
   }
 
   const hydrateList = () => {
-    if (!useStorage()) {
-      return
-    }
-
     const prevStorage = getStorage()
     const migratedStorageContents = getStorageContents(prevStorage).map((record) => {
       return migrateRecord(record)
@@ -129,7 +116,7 @@ import boot from '../frontend'
   }
 
   const configureLogger = (logger) => {
-    if (!logger || !useStorage()) {
+    if (!logger) {
       return
     }