relax SVN archive

Expansion and completion of the model-free chapter of the relax user manual.

A large number of changes have been made to complete the chapter and description of all model-free
sample scripts. The dauvernge_protocol.py script is now fully described.

Updated the http://www.nmr-relax.com/download.html webpage for the relax 1.3.15 news item.

This news item is located at https://gna.org/forum/forum.php?forum_id=2343.

Updated the http://www.nmr-relax.com/download.html webpage for relax 1.3.15.

Some small edits to the release checklist document.

Removed more maths from the HTML user manual section titles.

This is using the \latexonly and \htmlonly constructs to toggle titles.

Updated the API documentation to relax version 1.3.15.

Fix for the ANSI escape sequences for colouring text for when an isatty() method does not exist.

This is needed for the epydoc constructed API documentation as the redirection is a special epydoc
_Devnull object which has not isatty() method!

Fix for the creation of the HTML user manual http://www.nmr-relax.com/manual/index.html file.

Readded the http://www.nmr-relax.com/manual/index.html webpage.

Updated the relax HTML user manual to version 1.3.15.

This is located at http://www.nmr-relax.com/manual/index.html.