BUG: Calculate carrier frequency from NMRPipe files from origin
BUG: Calculate carrier frequency from NMRPipe files from origin

The carrier frequency does not seem to be reliably set in all
NMRPipe files, especially when data has been extracted with the EXT function
therefore the carrier frequency must be calculated from the origin of the
spectrum.

jjhelmus/nmrglue,kaustubhmote/nmrglue,atomman/nmrglue,kaustubhmote/nmrglue,atomman/nmrglue,jjhelmus/nmrglue