Merge a17t-redesign, kinda ts-ify setup.js

the web ui has been redesigned with the a17t toolkit, which imo looks a
lot better than bootstrap. This also brought a complete rework of the
web code, which now makes a lot more sense hopefully. the setup page is
still stuck with bootstrap, its not much of a priority but i'll rewrite
it eventually.

html/form-base.html

@@ -0,0 +1,9 @@
+{{ define "form-base" }}
+<script> 
+    window.usernameEnabled = {{ .username }};
+    window.validationStrings = JSON.parse({{ .lang.validationStrings }});
+    window.invalidPassword = "{{ .lang.reEnterPasswordInvalid }}";
+    window.URLBase = "{{ .urlBase }}";
+</script>
+<script src="js/form.js" type="module"></script>
+{{ end }}