relax SVN archive

Updated the API documentation (http://www.nmr-relax.com/api) to relax version 2.2.5.

Updated the HTML version of the manual at http://www.nmr-relax.com/manual to relax 2.2.5.

Added the PDF version of the relax manual to the repository.

Updated the version number to 2.2.5.

Redirected the download links for relax 2.1.1, 2.1.2, and 2.2.1.

These links at http://www.nmr-relax.com/download.html now point to
http://www.nmr-relax.com/download_request.html.

Backported the relax 2.2.5 changes file additions to trunk.

The command used was:
svn merge -r19097:19098 svn+ssh://bugman@.../svn/relax/tags/2.2.5 .

Updated the changes file for relax 2.2.5.

Updated the lib package __all__ list.

Some more unit test fixes.

Another attempt at fixing the unit tests of the pec module.