ui: Much elm work, such wow

- ui: Fix favicon
- webui: Changes to support serving Elm UI
- Static files now served from `/` mount point.
- Old UI handlers moved to `/serve` mount point, some will still be
  needed by the Elm UI; safe HTML and attachments for example.
- Update dev-start.sh for new UI, with tip on how to build it.
- ui: Detect browser host:port for websocket URL,
- webui: Remove unused mailbox handlers, rename routes
- Many routes not needed by Elm UI.
- `/serve/mailbox/*` becomes `/serve/m/*`.
- webui: Impl custom JSON message API for web UI,
- ui: Refactor Mailbox view functions,
- ui: Add body tabs for safe HTML and plain text,
- webui: Format plain text for new UI,
- ui: List attachments with view & download links,

pkg/server/web/helpers.go

@@ -54,11 +54,11 @@ func Reverse(name string, things ...interface{}) string {
 
 // TextToHTML takes plain text, escapes it and tries to pretty it up for
 // HTML display
-func TextToHTML(text string) template.HTML {
+func TextToHTML(text string) string {
 	text = html.EscapeString(text)
 	text = urlRE.ReplaceAllStringFunc(text, WrapURL)
 	replacer := strings.NewReplacer("\r\n", "<br/>\n", "\r", "<br/>\n", "\n", "<br/>\n")
-	return template.HTML(replacer.Replace(text))
+	return replacer.Replace(text)
 }
 
 // WrapURL wraps a <a href> tag around the provided URL