- Fix wrong version on launching with local pack
- Overhaul GUI
- Rework config logic so modpacks can ship default Cleanroom version & args
- Rewrite downloader to be multi-thread
- Ships with a default 0.3.13-alpha mmc pack so it can still work even you can't access GitHub
- Allow configuring central maven so relauncher works faster in some no CDN network
- Rework 8u51 support and make it barely working, and warn player about that
- Always pop a warning dialog provides latest JVM download link
- Add new certs since maven website renewed them