relax SVN archive

Modified the NOE system test to call the noe.spectrum_type() user function.

The spectrum_ids have also been changed to avoid user confusion (when these changes are ported to
the sample script).

Fixes for the volume integration with no replicated spectra.

Partial implementation of the error_analysis() code

The 2 categories now supported are both peak height and volumes when no spectra are replicated.

Updated the version number to 1.2.15.

Manually ported the 1.2.14 tag CHANGES file changes to the 1.2 line.

The command used was:
svn merge -r8033:8034 svn+ssh://bugman@.../svn/relax/tags/1.2.15 .

Updated the CHANGES file for relax 1.2.15.

Manually ported the 1.2.14 tag CHANGES file changes to the 1.2 line.

The command used was:
svn merge -r7122:7123 svn+ssh://bugman@.../svn/relax/tags/1.2.14 .

This matches r8032.

Manually ported the 1.2.14 tag CHANGES file changes to the 1.2 line.

The command used was:
svn merge -r7122:7123 svn+ssh://bugman@.../svn/relax/tags/1.2.14 .

relax version 1.2.15.

This is a minor bug fix release.

Reverted r8029. This 'svn cp' went to the wrong place!

The command used on a checked out copy of the 1.2.14 tag was:
svn merge -r8029:8028 .