new: implement pool IGNORE option to mp-pool

mtsc-common/common.sh

@@ -230,3 +230,11 @@ check_pkg_vars() {
 
   return 0
 }
+
+# check if a package should be ignored
+should_ignore(){
+  for i in "${IGNORE[@]}"; do
+    [ "${i}" == "${1}" ] && return 0
+  done
+  return 1
+}