relax SVN archive

Added checks for a current data pipe to a number of GUI user function pages.

This prevents relax errors when trying to launch the user functions but when no data pipes exist.

The screen is no longer cleared prior to relax execution on MS Windows.

This prevents the Windows PowerShell history from being wiped out.

Fix for the MS Windows BAT file so that relax can be launched from the Windows PowerShell.

Fix for the dauvergne_protocol model-free auto-analysis with the deletion of data pipes.

Now only the data pipes created by dauvergne_protocol are deleted. This fixes the problem whereby
data pipes from other analyses are deleted by dauvergne_protocol, breaking the GUI.

Bug fix for the Rx auto-analysis GUI test.

The read only spectrum ID combobox values should be set with SetStringSelection().

Improved the RelaxError messages in validate_sequence().

The invalid data is now printed so that the user can see why it is invalid.

Fix for the spin viewer window for MS Windows.

The get_info() method now catches if no item is selected in the tree before trying to get the Python
data from it. Asking for Python data from a missing TreeCtrl item ID works on GNU/Linux and Mac OS
X, but not on MS Windows.

Bug fix for MS Windows - the main relax window is now maximized on start up.

Improved the print outs of the scons 'binary_dist' target for Mac OS X.

Modified the 'clean' scons target to remove the py2app build and dist directories.