Added missing expected attr count to HelpCommand class
Fixed pre-command execution -> exit after command exec
Fixed help string printing
Added prefix helpers
Added prefix parsing in CommandParser class
The TagCommand command has a prefix
Replaced tree reading by more abstract and more powerful code. Functionality remains the same
Refactored #subs_from_path() into smaller chunks
Merge branch 'refactor-tree_reading'
Merge branch 'fix-help_command'
Merge branch 'command_prefixes'