note a few todo items.

js/pixl/README.md

@@ -15,3 +15,13 @@ it's live at <http://pixl.papill0n.org>.
`pixl` in 3 dimensions. you can even import the data from pixl.
see it live at <http://pixl.papill0n.org/3>.
## todo
* code sharing (especially for worlds created and dynamics, but also for
  libraries/modules that could be shared)
* multiplayer backend as for pixl
* live-editing from a built-in editor (similar to firefox' scratchpad,
  but on the page. should also support saving code to `localStorage`.)
* bug: sometimes when moving the mouse to certain positions (edges of
  the screen?) the camera rapidly alternates between two positions