relax SVN archive

Copyright notice update.

Updated the interatom.unit_vectors user function description to add the text '3D structure'.

This is in response to the http://thread.gmane.org/gmane.science.nmr.relax.user/1547 relax-users
mailing list message and the change is to clarify the usage of the user function.

Initial implementation of the double rotor frame order model target function.

The target function func_double_rotor() has been created as a copy of the func_rotor_qrint() method,
modified for the double rotor model. Modifications will likely be needed as the
compile_2nd_matrix_double_rotor() and pcs_numeric_int_double_rotor() functions are implemented.

Better support for the parameters of the double rotor frame order model.

Updated the news announcement links for relax version 3.1.4 at http://www.nmr-relax.com/download.html.

The correct link is https://gna.org/forum/forum.php?forum_id=2433.

Updated the relax version number to 3.1.4 on the http://www.nmr-relax.com/api/index.html webpage.

Updated the relax API documentation at http://www.nmr-relax.com/api/3.1/ to version 3.1.4.

Removed links for many old relax releases.

This is for the webpage http://www.nmr-relax.com/download.html and the links for the old releases
now all point to http://www.nmr-relax.com/download_request.html.

Updated the relax HTML manual at http://www.nmr-relax.com/manual/index.html to version 3.1.4.

Updated the http://www.nmr-relax.com/download.html webpage for relax 3.1.4.