[IGSMAIL-6413] Rapid clock file replacements: 1637_2 till 1640_3

[jim.ray at noaa.gov]

Author: IGS Analysis Center Coordinator

The IGS Rapid clock files (igrwwwwd.clk) for the period GPS wk
1637 d 2 through wk 1640 d 3 were replaced in order to correct
the header record "SYS / PCVS APPLIED" to give the correct
antenna calibration file, namely igs08_1629.atx.  There were no
changes to the actual numerical values in these files.  Updated
clk files were sent to all four IGS Global Data Centers.

We thank Narve Schipper Kjørsvik for bringing this error to our
attention and we apologize for any confusion that might have
been caused.