relax SVN archive

Updated the download webpage http://www.nmr-relax.com/download.html for relax version 2.2.4.

Updated the relax API documentation (http://www.nmr-relax.com/api/) to version 2.2.4.

Updated the relax HTML manual to version 2.2.4.

This will appear at http://www.nmr-relax.com/manual/.

Added the relax 2.2.4 PDF manual to the repository.

Updated the version number to 2.2.4.

Backported the relax 2.2.4 CHANGES file to trunk.

The command used was:
svn merge -r18837:18838 svn+ssh://bugman@.../svn/relax/tags/2.2.4 .

Updated the CHANGES file for relax 2.2.4.

relax version 2.2.4.

This is a major bugfix release fixing system test and unit test bugs in the Mac OS X application,
fixed for the RMSD related functions for systems with old Numpy versions installed, the system
information printout fixes when the relax path contains spaces, Python 3 fixes throughout, some
problems with the model-free auto-analysis under certain conditions, and fixes for the value.write
user function when very small values are encountered (for example the field-strength independent Rex
values from a model-free analysis).

Deletion of the frame_order.domain_to_pdb user function.

The redesign of the frame_order.pdb_model user function will make frame_order.domain_to_pdb
obsolete. The user function is ugly anyway as it forces a user to create a separate PDB file for
each domain.

Modifications to the frame_order.pdb_model user function backend.