fix errors in NetcdfFilewriter.openExisting()
Merge remote-tracking branch 'origin/target-4.3.18' into target-4.3.18
unit test failure
added AFWA grib1 table version 133
Merge remote-tracking branch 'origin/target-4.3.18' into target-4.3.18
Added AfwaTables (grib1) to handle center 57 special level handling;
Ncep Table3 (levels) had bug, subst Datum for Desc field.
 AfwaTables now handling gen process and subcenter names
Integer.compare requires Java7, move methods to Misc
Integer.compare requires Java7, move methods to Misc