100% Chinese translation, nw.js update, and minor improvements

✨ New Features

• New tweening functions (elastic, bounce, and with backward motion) for ct.tween by kkornushin
• Two UI themes Pooxel Green and Pooxel Blue for that retro feel 👾

⚡️ General Improvements

• Chinese Simplified 100% translated for branch v1.x (#246 & #248 by @emaoshushu)
• Use nw.js' nightly build 25eea59. Solves the issue with restarting ct.js after running a game in it.

🐛 Bug Fixes

• Fix exts object missing on newly created copies.
• Fix formatting problem at ct.place docs > Tracing functions > ct.place.traceRect.
• Partially fix memory leaks in paricle emitter editors.

📝 Docs

• Use cgroup instead of ctype in ct.place typings and docs to remove ambiguity with ctypes and regular types
• 🐛 Fix wrong function names at ct.noise