Move SFTReferenceLibrary to lalpulsar?

@karl-wette I'd like to move the guts of lalapps_SFTvalidate into a lalpulsar XLAL function to make them SWIG-accessible, similar to what we've done with various other executables. But its main loop relies on error codes and some helper functions defined in lalpulsar/src/SFTTools/SFTReferenceLibrary.(ch). Do you think there is a necessary reason for this module being where it is, besides history, or would it be fine to move it into lalpulsar/lib? With minor Makefile and header-include amendments, this seems not to break either of the few other lalapps codes that rely on it. Also, if the sources for lalapps executables have to move to lalpulsar/bin soon, this would seem logical anyway.

(An alternative, larger change would be to phase out that module, in the few caller codes replace any of its functions which already have near-duplicates within SFTFileIO or SFTUtils, and port over the bits that aren't duplicated. But a) that would be a lot more work, and b) as the name "Reference" implies, there's a point to this remaining an independent implementation of some of the lowest-level functions, in case we ever break the more commonly used variants.)