relax SVN archive

Bug fix for both generic_fns.state unit tests.

Renamed the file_path class method to the get_file_path module function.

Renamed relax_io.mkdir to relax_io.mkdir_nofail and converted it from a class method to a function.

Converted the open_write_file class method into a module function.

Converted the open_read_file class method to a function.

Converted the log class method to a function.

Added a simple docstring to the relax_io module.

Fix for the renaming of io.py to relax_io.py.

The module renaming has been taken into account as well as the eventual removal of the IO class and
the conversion from class methods to module functions.

Added some comments for the import statements.

The open_read_file function is now imported as well.