Porting UPP for gfs v16 on wcoss2 (#420)

* Add changes for building executable on wcoss2.

* Add changes for buding upp lib on wcoss2.

* Add changes for building upp lib on wcoss2.

* Update hdf5 and netcdf modules.

* Upgrade manage_externals to new version which works for python 3.8.5.

* Remove jlogfile in workflow scripts.

* Changes for overriding module versions from upstream setting.

* Changes for overriding module versions from upstream setting for
building upp lib.

* Update for POSTGRB2TBL default setting.

* Update for LMod compliance.

* Remove v8.0.0-wcoss2 and lib-wcoss2; correct typo in upp_wcoss2.lua and
post_wcoss2.lua.

* Remove jflofile per Kate's comments

* Change GTG checkout to submodule and remove manage_externals (#5)

* Retire manage_externals for GTG checkout

- remove manage_externals copy from repo
- remove associated Externals.cfg file
- replacing GTG checkout with submodules

Refs: #363

* Add UPP_GTG submodule

- created .gitmodules file via git submodule add command:
git submodule add https://github.com/NCAR/UPP_GTG sorc/post_gtg.fd
- new post_gtg.fd subfolder added (empty before submodule checkout)

Refs: #363

* Updating submodule pointer of GTG to ncep_post_gtg.v2.0.4

* Teak makefile_lib.

Co-authored-by: Wen Meng <Wen.Meng@clogin02.cactus.wcoss2.ncep.noaa.gov>
Co-authored-by: Kate Friedman <kate.friedman@noaa.gov>

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "sorc/post_gtg.fd"]
+	path = sorc/post_gtg.fd
+	url = https://github.com/NCAR/UPP_GTG

jobs/JGLOBAL_ATMOS_NCEPPOST

@@ -128,7 +128,7 @@ export SLEEP_INT=5
 # Run relevant exglobal script
 env
 msg="HAS BEGUN on `hostname`"
-postmsg "$jlogfile" "$msg"
+postmsg "$msg"
 $LOGSCRIPT
 
 
@@ -148,7 +148,7 @@ if [ -e "$pgmout" ]; then
 fi
 
 msg="ENDED NORMALLY."
-postmsg "$jlogfile" "$msg"
+postmsg "$msg"
 
 
 ##########################################

jobs/J_NCEPPOST

@@ -24,11 +24,6 @@ mkdir -p $DATA
 cd $DATA
 export KEEPDATA=${KEEPDATA:-NO}
 
-####################################
-# File To Log Msgs
-####################################
-export jlogfile=${jlogfile:-${COMROOT}/logs/jlogfiles/jlogfile.${job}.${pid}}
-
 ####################################
 # Determine Job Output Name on System
 ####################################