relax SVN archive

No spins are deselected if no spins / residues are indicated.

A fix has to be done if spins /residues are deselcted. Best will be to create a file listing these residues / spins.

Replicated spectra are set correctly.

Relaxation times are converted into float objects (from strings).

Proton and hetero nucleus type is specified in read intensity function.

The sequence is loaded from a pdb file, if provided.

New arguments are accessible for all functions.

The class Relax_fit reads in the type of calculation (R1 or R2), the frequency, results directory, pdb file and unresolved residues.

Current date was added to pipe name to allow multiple rx calculations during the same session.

Proper openfile dialog was included to the function to open a global pdb file.

A global pdb file can be loaded through the menu Molecule>Load PDB File.