[Nightly] Update v0.7.2237a

• Implemented group system in the filesystem, now visible with ls -l. You can create groups for users and define groups for files or folders. With this change, the problem of the previous update was solved in which non-root users could barely move around the system, receiving messages of "permission denied".
  
  
• Added chown command, to change the owner of a file.
  
  
• Added chgrp command, to change the group of a file.
  
  
• Added groupadd and groupdel commands. To add and delete a group of a specific user respectively.
  
  
• Added methods computer.create_group, computer.delete_group, file.set_owner, file.group, file.set_group.
  
  
• Added command groups and method computer.groups to list the current groups to which a user belongs.
  
  
• Fixed bug in which less competent administrators were not applying variations of permissions in most types of networks.
  

NOTE: the documentation of the new methods and commands will be added in the next update. The source code of the new commands is available in the Manual.