v2.0.0-beta3

A few things...

• automatically disable the unpublished integrated-learn-environment package if it's installed
• remove Atom's welcome package from build
• cleanup builds for linux
• bump learn-ide-tree to 1.0.6
  • add Refresh command
  • expand to active file on atom_open
  • fix atom_open error on directories that lack a readme
  • fix indexOf error with ping & pong across multiple windows
• bump single-socket to 0.0.8
  • silence node-ipc logger

Also, other stuff! 🎉