relax SVN archive

Fix for the sample label matching - this is only performed if the sample label is given.

The sample conditions label is now being used to select the correct BMRB saveframes to read.

Removed the unused index.html.

Fix for the Rex scaling - the factor was incorrect!

Square brackets and commas are now also removed from the BMRB molecule name.

Fix for generic_fns.mol_res_spin.bmrb_read() for when no molecule name is present.

The sample_conditions arg to bmrb.read() is now set to None.

This is to allow single condition files to be always read.

The back-end of the bmrb.read() user function is now recognising the sample_conditions arg.

The bmrb.read() user function now accepts the sample_conditions arg.

The model-free bmrb_read() now accepts a sample conditions arg and checks that only one is loaded.