relax SVN archive

Modified the int_col arg to spectrum.read_intensities() to allow for lists of integers.

Wrote 15 arg unit tests for the spectrum user functions.

Created the new error class RelaxNoneIntListIntError.

Created the skeleton module for arg unit tests of the spectrum user function class.

Finished of the massive docstring of the spectrum.error_analysis() user function.

Another import error fix.

Import error fix.

Import fix for generic_fns.spectrum.

Renamed the generic_fns.intensity module to generic_fns/spectrum.

Rewrote the spectrum.error_analysis() user function docstring.

This is still missing 3 sections for error analysis with the volume integration methods.