add options() method, resolve #2

src/Options.php

@@ -0,0 +1,16 @@
+<?php
+
+namespace ArchTech\Enums;
+
+trait Options
+{
+    /** Get an associative array of [case name => case value]. */
+    public static function options(): array
+    {
+        return array_reduce(static::cases(), function ($options, $case) {
+            $options[$case->name] = $case->value;
+
+            return $options;
+        }, []);
+    }
+}