relax SVN archive

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.

Replaced how a global analysis average results from a previous run to instead take the median.

This is to prevent averaging extreme outliers, and instead take the median of the previous result.
This was discussed in: https://mail.gna.org/public/relax-devel/2013-10/msg00009.html.

Changed a unit test and systemtest, where a change from the atan to atan2 function to calculate theta can give differences to the 15 decimal.

Updated the news announcement links for relax version 3.1.7 at http://www.nmr-relax.com/download.html.

The correct link is https://gna.org/forum/forum.php?forum_id=2448.

Updated the http://www.nmr-relax.com/download.html webpage for relax 3.1.7.

Updated the relax version number to 3.1.7 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 3.1.7.

Updated the relax HTML manual at http://www.nmr-relax.com/manual/index.html to version 3.1.7.

Replaced funtion atan(omega1 / Delta_omega) with atan2(omega1 , Delta_omega), to make sure returned theta values are between 0 and pi.

This was done in the function return_offset_data() in the specific_analyses of relax_disp.
This was discussed in: http://thread.gmane.org/gmane.science.nmr.relax.devel/5210.

Shifted two functions from pipe_control.angles into the new lib.geometry.angles module.

This is the fold_spherical_angles() and wrap_angles() functions which are not related to the relax
data store and hence can be made independent.