relax SVN archive

Ported r5815 from the 1.2.13 tag.

The command used was:
svn merge -r5815:5816 svn+ssh://bugman@.../svn/relax/tags/1.2.13 .

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r5816 | bugman | 2008-04-19 13:04:23 +0200 (Sat, 19 Apr 2008) | 3 lines

Updated the CHANGES file for relax version 1.2.13.
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Ported r3532 from the 1.2.12 tag.

The command used was:
svn merge -r3532:3533 svn+ssh://bugman@.../svn/relax/tags/1.2.12 .

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r3533 | bugman | 2007-11-17 12:25:43 +0100 (Sat, 17 Nov 2007) | 3 lines

Updated the CHANGES file for relax 1.2.12.
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Ported r7425 from the 1.3.1 tag.

The command used was:
svn merge -r7425:7426 svn+ssh://bugman@.../svn/relax/tags/1.3.1 .

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r7426 | bugman | 2008-09-28 22:32:16 +0200 (Sun, 28 Sep 2008) | 3 lines
Changed paths:
M /tags/1.3.1/docs/CHANGES

Updated the CHANGES for relax version 1.3.1.
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Updated the CHANGES for relax version 1.3.1.

relax version 1.3.1.

Well, this one's going to take a while to summarise. 4398 revisions since 1.3.0, and 2 years of 1.3
line development!

Added the add_struct() stub method to the structural API base class.

Renamed all __add_struct() methods to add_struct().

Removed an unused import.

Changed create_diff_tensor_pdb() to call the __add_struct() structural object method.

Modified __add_struct() to use Structure_container() if the structural object is not provided.