relax SVN archive

Updating the self.system_cwd_path when a directory change is observed.

Letting the current working directory be printed in the statusbar in the bottom.

Letting the lib.system.cd function notify the observer, when chanding directory.

Modifying the userfunction system.cd() not to show the result to STDOUT.

Adding an observer for current working directory.

Changing to a filedialog for the userfunction system.cd()

Adding af verbose flag to lib.system.pwd() function.

Adding a toolbar button for changing the current working direxctory.

Storing the current working directory as a GUI variable.

Adding a verbose True/False for the lib.system.pwd() function.