relax SVN archive

Added systemtest to search a dir for NMRPipe .ft2 files, extract noise, and write to file.

Added function to search a dir for NMRPipe fourier transformed files, call showApod on them, extract RMSD and write to file.

Added function to lib.io to sort a list of filenames into human-understandable alphanumeric order.

Systemtest added for checking the writing of 'Noise Std Dev' from showApod to file.

task #7826(https://gna.org/task/index.php?7826): Write an python class for the repeated analysis of dispersion data.

Added function to write 'Noise Std Dev' from showApod to file, and fix documentation.

Added systemtest to check the extraction of 'Noise Std Dev' from showApod in NMRPipe suite.

Added function to extract the 'Noise Std Dev' from NMRPipe showApod.

Added systemtest Relax_disp.test_show_apod_extract to call the showApod from NMRPipe.

To the lib function of spectrum.nmrpipe, added function to call the NMRPipe program showApod, to get the output from the program.

Added dependency check for the NMRPipe showApod program.

This program can be really usefull, if processing a large amount of data, and quickly needs to asses the RMSD of the spectrum.