this subroutine evaluates the nutation series and returns the
values for nutation in longitude and nutation in obliquity for
j. m. wahr's nutation series for axis b for earth model 1066a.
written by g.kaplan of usno from wahr's thesis results.
modified 13 april 81 by r.king of mit to agree with the slightly
different values given in wahr's paper in geophys.j.r.astr.soc.
added to pep 1989 december by j.f.chandler.

arguments
t    = tdb time in julian centuries since j2000.0 (in)
dpsi = nutation in longitude in radians (out)
deps = nutation in obliquity in radians (out)