relax SVN archive

Fix for bug #20198 (https://gna.org/bugs/?20198) - the relaxation data back-calculation error.

The problem was that the call to the model-free overfit_deselect() method was deselecting any spins
lacking relaxation data! This should not happen, as no spins need to have relaxation data for this
calculation.

Updated the Mac OS X distribution to 2.1.1 (http://www.nmr-relax.com/download.html).

Updated the 32-bit MS Windows download to 2.1.1 (http://www.nmr-relax.com/download.html).

Updated the 32-bit GNU/Linux distribution to 2.1.1 on the download page

http://www.nmr-relax.com/download.html.

Updated the new forum link for relax 2.1.1 on the download page (http://www.nmr-relax.com/download.html).

Updated the online API documentation (http://www.nmr-relax.com/api/) to relax version 2.1.1.

Updated the online HTML user manual to version 2.1.1 (http://www.nmr-relax.com/manual/index.html).

Started to update the download page for relax 2.1.1 (http://www.nmr-relax.com/download.html).

Added the relax 2.1.1 user manual to the repository.

Updated the relax version number to 2.1.1.