relax SVN archive

Raising an error if plotting dispersion curves, and no model is saved.

Added the expectation of raising an relax error, if trying to plot and no model information is stored.

In the function of r2eff_read, in data module of the dispersion, added the possibilities to read
r2eff values which are replicated.

This is done first checking if the dispersion key exists in the r2eff dictionary.
If it exists, continue add 0.001 to the frequency until a new possibility exists.

This should help handle multiple R2eff points, as separate values and not taking any decision to average them.

Added further tests to -s Relax_disp.test_paul_schanda_nov_2015.

This will show that replicates of R2eff values is not handled well.

Expanded a comment about why 1 is subtracted in a test.

In the systemtest of -s Relax_disp.test_paul_schanda_nov_2015, added a test of counting the R2eff values.

This shows that the replicaceted R2eff at 950 MHz/4000 Hz point is overwritten.

A solution could be to change the dispersion frequency very little, to allow the addition of the datapoint.

Small fix for an example script.

Making sure that the replicated 4000 Hz point fpr the 950 MHz experiment is not overwritten.

Made additional check in sequence reading, that "nan" values are skipped.

Added systemtest relax -s Relax_disp.test_paul_schanda_nov_2015 -d.

This will cathc the loaning of "nan" values.