relax SVN archive

Fixes for the interatomic_loop() calls in the interatom selection and deselection user functions.

Fixes for the interatomic_loop() iterator when using selection strings.

The previous approach did not work!

Converted the population model RDC test data to the interatomic data design.

The RDC lists now consist of the two spin ID columns and a data column.

Removed the SRLS reference from http://www.nmr-relax.com/refs.html.

Fix for the interatomic data container is_empty() method for the new variables and methods.

Interatomic data containers can now be selected and deselected.

The user functions select.interatom and deselect.interatom have been created mimicking the
equivalent select.spin and deselect.spin functions. Each interatomic data container now has a
select flag.

Modified the interatomic_loop() function so that spin IDs can be used to restrict the looping.

Fix for the N-state model _minimise_bc_data() method for the interatomic data design.

A number of fixes for the N-state model target functions for the interatomic data design.

Converted all of the rdc related functions to the interatomic data container design.