17 ENHANCEMENT: * Chain tool behaves like magic pen: you can make loops and closed paths 16 ENHANCEMENT: * Add sharing to magic pen and polygon * Clean up of some internals 15 ENHANCEMENT: * Added support for collaboration BUG FIX: * Fix problem with pause/play button 14 ENHANCEMENTS: * New translations * GTK3 conversion by Ignacio Rodriguez 13 ENHANCEMENTS: * Added palettes to set density, bouciness, and friction (w/Sai Vineet) * Added palette to set motor speed, rotation (w/Sai Vineet) * Added chain tool (w/Sai Vineet) BUG FIX: * Updated Box2d version to eliminate some memory leaks (Sai Vineet) 12 ENHANCEMENTS: * Added option to joints to set collideConnected = False * Added clear_all (Sai Vineet) * Added tracking (Sai Vineet) * Added tracing (Sai Vineet) * Added erase traces (Sai Vineet) * Added save/restore of pens and traces (Sai Vineet) BUG FIXES: * Removed cjson dependency for elements * pep8 cleanup (Sai Vineet) 11.9 * Removed cjson dependency for elements * Added option to joints to set collideConnected = False * Added clear_all (svineet) * Added tracking (svineet) * Added tracing (svineet)