📝 Added error.sh documenting how error func works

scripts/error.sh

@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+error() {
+    printf "error: %s\n" "$1" 1>&2
+    # second argument is not required (defaults to 2)
+    # if second argument is provided, it must be a number,
+    # this is to assign an error code number to the exit command
+    ${2:+exit $2}
+}
+error "$@"