Added more ideas

TODO.md

@@ -7,3 +7,16 @@
 * keyboard shortcuts (not the ugly `<key>Shift</key>+<key>F8</key>)
 * TC dependency issues
 
+
+### Data model ###
+
+* step identity
+
+
+### WUI ###
+* data persistence (HTML5)
+
+
+## Implementation ##
+
+* everything! :)