Remove outdated builtin editors list... (filp#520)

* Remove outdated builtin editor...

... and replace by the the dedicated page url.

* fix wording.

docs/API Documentation.md

@@ -367,11 +367,8 @@ PrettyPageHandler::addResourcePath(string $resourcesPath)
 // Sets an editor to use to open referenced files, either by
 // a string identifier, or as an arbitrary callable that returns
 // a string or an array that can be used as an href attribute.
-// Available built-in editors are:
-// - sublime
-// - emacs
-// - textmate
-// - macvim
+// Available built-in editors can be found here: https://github.com/filp/whoops/blob/master/docs/Open Files In An Editor.md
+
 PrettyPageHandler::setEditor(string $editor)
 PrettyPageHandler::setEditor(function ($file, $line) { return string })