relax SVN archive

Bug fix for the Combo_list.GetValue() method - it can now handle no user input cleanly.

Added the spectrum.integration_points user function backend so that the auto-generated class can work.

This raises a RelaxImplementError as this is not implemented, but allows the front end to be
accessible.

Updated the download page for version 1.3.16 (http://www.nmr-relax.com/download.html).

Added a direct link to the HTML manual in the webpages' menu (http://www.nmr-relax.com/menu.html).

Updated the API documentation to version 1.3.16 (http://www.nmr-relax.com/api/).

Updated the relax HTML user manual to version 1.3.16 (http://www.nmr-relax.com/manual/index.html).

A small edit of the "The universal solution" subsection title of the model-free chapter.

This is for the relax HTML user manual (http://www.nmr-relax.com/manual/Model_free_analysis.html).

Fix for the HTML version of the relax user manual (http://www.nmr-relax.com/manual/).

The model-free chapter subsection on the universal solution was causing Latex2html to die! This is
the same as the fixes of r15816, but the \widehat maths command was recently reintroduced into this
new section.

Fix for the creation of the HTML user manual (http://www.nmr-relax.com/manual).

The shell command for renaming the relax_user_manual.html file to index.html had a typo and was not
working!

Ported the HTML user manual fix of r16225 from the 1.3.16 tag.

The command used was:
svn merge -r16224:r16225 svn+ssh://bugman@.../svn/relax/tags/1.3.16 .

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Removed more maths from the section titles of the HTML user manual.

This is an attempt at fixing the image brokenness of the HTML manual!
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