RRFSv1.0 Product cleanup: removal of retired products from fv3lam_rrf…

…s.xml (#909)

* removed  <table_info>NCEP</table_info> for ULWRF to use the official WMO ID rather than the dupilcate NCEP local use ID

* removed <table_info>NCEP</table_info> from REFZR, REFZI, BMIXL, and CNWAT to use WMO grib2 ids

* removed <table_info>NCEP</table_info> from SNOWC, SFEXC, SSRUN, BGRUN, FRICV, CD, SNOHF, PEVAP, TCOLI in order to use WMO id over NCEP local use ID.

* removed <table_info>NCEP<table_info> from SNFALB, CDLYR, USWRF, DSWRF, DLWRF, VWSH, TCOLR, TCOLS, UPHL

* removed <table_info>NCEP<table_info> from MSTAV in post_avblflds.xml to use WMO grib2 id for RRFS

* removed duplicate CNWAT NATLEV entry in fv3lam_rrfs.xml.

* updated fv3lam_rrfs.xml and parm/postxconfig-NT-fv3lam_rrfs.txt to remove products no longer needed in the RRFS.

* changed precision in SSRUN

* fixed SSRUN precision in flat file

* removed LSPA and SNOWC from NATLEV