connected v0.9.7

Version 0.9.7 of connected mostly fixes the wrong file sorting in the Welcome Screen.

• upgraded to Unity 6
• fixed Welcome Screen file list (now using last write time instead of last access time)
• added option to change the file extension of the created JSON files
• added "file_extension" to configuration file
• added a tiny bit of space to the SCRIPT node so the resizer doesn't overlap a button anymore