Add more items to the editor, fix its buttons, do smart drawing

index.html

@@ -23,9 +23,8 @@
         <h2 id="level-pack-name">Chip's Challenge Level Pack 1</h2>
         <nav>
             <button id="main-change-pack" type="button">Change pack</button>
-            <!--
-            <button id="player-edit" type="button">Return to editor</button>
-            -->
+            <button id="player-edit" type="button">Edit</button>
+            <button id="editor-play" type="button">Test</button>
         </nav>
     </header>
     <header id="header-level">
@@ -96,7 +95,6 @@
         </header>
         <div class="level"><!-- level canvas and any overlays go here --></div>
         <div class="controls">
-            <button id="editor-test" type="button">Test</button>
         </div>
         <div class="palette"></div>
         <!-- TODO: