got a working merge of the who icd10 and cms icd10cm code spaces. This merge has a single entry for each code, prefering the WHO version when available.

non-db_data_sources/GBD and ICD-10_(2019 version)/merge_icd-versions.sh

@@ -0,0 +1,10 @@
+#!/bin/bash
+
+icd10_who="./WHO ICD-10 (2019)/icd10-2019_categories_only.psv"
+icd10cm_cms="./icd10cm_codes_addenda_2019/icd10cm_codes_2019.psv"
+
+#concatenate the two files
+#then lexically sort them by first column and then second column(reversed)
+#then sort/unique based on first column
+#then save to file
+cat "$icd10_who" "$icd10cm_cms" | sort -t "|" -k 1,1 -k 3,3r | sort -u -t "|" -k 1,1 > icd10_combined-who-cms.psv