Add a wrapper that retries hdiutil with progressive timeout

This seems to be a common workaround for CPack issue on macOS. 

Script has 10 attempts and in the worst case it will take 55 seconds for it to fail.

scripts/build/macOS/hdiutil_wrapper.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+
+# A special wrapper for hdiutil, that retries hdiutil call with
+# the progressive timeout. 
+# This seems to be the common workaround for the CPack problem
+
+counter=0
+max_retries=10
+
+hdiutil $@
+
+while [ $? -ne 0 ]; do
+    ((counter++))
+
+    if [[ $counter -eq $max_retries ]]; then
+        exit 1
+    fi
+
+    sleep $counter
+    hdiutil $@
+done