relax SVN archive

Shifted check_entries() and whichmodel() from select_model_calc to auto_model_free.

These are specific to the automatic model-free protocol, so do not need to be in a separate module.
They were also converted from functions to methods.

Removed the unused analyses.select_model_calc import.

Deleted the exec_model_free() from the relax_gui module.

It is now in the analyses.auto_model_free module.

Modified the call to savefile.

Keyword args are now used and the relax installation directory is not supplied as the default
opening directory.

Modified savefile() to be up to relax' standards and to match the operation of openfile().

The current working directory is changed if the directory arg is not given.

Modified StructureTextCtrl to not supply the directory arg to openfile().

The current working directory is used and changed if no directory arg is supplied to openfile().

Converted the openfile() args to keyword args.

Reverted the last revision (r10374) as the directory arg was lost.

The command used was:
svn merge -r10374:10373 .

This directory arg will be useful in other parts of the GUI.

Modified the operation of openfile().

The directory is now set to getcwd(), and any moving around in the file structure in the dialog by
the user causes the current working directory to change (using chdir()).