relax SVN archive

Added a system test for the creation of an XH bond vector distribution.

This test mimics the script used to create figure 7.8 of my PhD thesis
(http://eprints.infodiv.unimelb.edu.au/archive/00002799/).

Fix for bug #12670 (https://gna.org/bugs/index.php?12670).

This bug was reported by Michael Funk (mifu att nmr dot mpibpc dot mpg dot de).

The problem was that the relaxation curve-fitting return_error() method was returning the global
cdp.sigma_I error structure - which does not exist for all error types - when it should have been
returning the spin specific error structure.

Activated the system test catching bug #12670 (https://gna.org/bugs/index.php?12670).

This bug was reported by Michael Funk (mifu att nmr dot mpibpc dot mpg dot de).

The script for reproducing bug #12670 (https://gna.org/bugs/index.php?12670) now works.

This bug was reported by Michael Funk (mifu att nmr dot mpibpc dot mpg dot de).

Added all the files necessary to reproduce bug #12670 (https://gna.org/bugs/index.php?12670).

This bug was reported by Michael Funk (mifu att nmr dot mpibpc dot mpg dot de).

The script needs to be modified to point to the correct locations and needs to be activated as a
system test.

Created a directory to store sequence data.

Continued the implementation of the reading of the generic peak intensity file.

The delays and intensities can now be read for the different peaks.

The remaining tasks include passing these information (delays + intensities) to relax...

Continued to implement the reading of the generic peak intensity file.

The code now calculates the number of delays (and associated intensities) input.

The remaining tasks include sorting the delays and intensities, which is different from when other
peak intensity files are used (e.g. XEasy, Sparky, nmrview) since the delays are part of the input
file header (in the case of the generic file).

Added more system tests for the reading of an XEasy peak list with different spins.

Not sure if defining new functions was absolutely needed, but it works.

Closure of the spectral_errors branch.