Merged revisions 20807 via svnmerge from 
svn+ssh://bugman@svn.gna.org/svn/relax/trunk

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  r20807 | bugman | 2013-09-04 17:47:45 +0200 (Wed, 04 Sep 2013) | 3 lines
  
  Created the pipe_control.spectrum.test_spectrum_id() function for checking if a spectrum ID exists.
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Merged revisions 20809-20811 via svnmerge from 
svn+ssh://bugman@svn.gna.org/svn/relax/trunk

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  r20809 | bugman | 2013-09-04 17:59:10 +0200 (Wed, 04 Sep 2013) | 5 lines
  
  Renamed pipe_control.spectrum.test_spectrum_id() to check_spectrum_id().
  
  A bug in the function was also removed, and the other code in the module now uses this function.
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  r20810 | bugman | 2013-09-04 18:05:59 +0200 (Wed, 04 Sep 2013) | 6 lines
  
  Created the pipe_control.mol_res_spin.check_mol_res_spin_data() function.
  
  This will check for the existence of molecule, residue and spin data and raise a RelaxError if none
  exists.
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  r20811 | bugman | 2013-09-04 18:07:14 +0200 (Wed, 04 Sep 2013) | 5 lines
  
  Simplification of the data checks in the pipe_control.spectrum module.
  
  This is using the new pipe_control.*.check*() functions.
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Modified the Relax_disp.test_dpl94_data_to_dpl94 system test for a relax_disp.exp_type change.

This is so that the relax_disp.exp_type user function associates the experiment types with a
spectrum ID.  This follows from http://thread.gmane.org/gmane.science.nmr.relax.devel/4530.
Clean up and expansion of the dispersion experiment type variables.
Another change to the dispersion experiment type variables.