relax SVN archive

Switched from os.spawnlp to os.popen3 for proper IO redirection.

This allows the system tests to capture Modelfree4's STDOUT and STDERR streams, as they are fused
into relax's.

Many fixes for the Modelfree4 execution system test script.

Bug fix for the palmer.py sample script.

The model_selection() user function args were wrong.

Converted execute() to the new design.

Converted create_run() to the new design.

Converted the create_mfmodel() and create_mfpar() functions to the new design.

Converted create_mfdata() to the new design.

Converted create_mfin() to the new design.

Converted the last pieces of create() to the new design.

Fix for the check of the constraints arg in palmer.create().