Allow spawn of specified package/app

         <form method=post action=/sites/machines>
         <label><small>Name</small><br>
         <label class=bounding><input type=text name=name></label></label>
-        <input type=hidden name=package value=canopy-platform>
-        <input type=hidden name=app value=canopy:app>
-        <div class=buttons><button>Spawn Machine</button></div>
+        <label><small>Package</small><br>
+        <label class=bounding><input type=text name=package></label></label>
+        <label><small>App</small><br>
+        <label class=bounding><input type=text name=app></label></label>
+        <div class=buttons><button>Spawn</button></div>
         </form>
     $else:
         <p>Add <code style="background-color:#073642;border-radius:.25em;font-weight:bold;padding:0 .25em .125em .25em;"><small><small>DIGITALOCEAN_TOKEN</small></small></code> to <a