added confirmation helper

helper/get_confirmation

@@ -0,0 +1,16 @@
+#!/bin/bash
+#
+# confirmaiton helper
+#
+# @params
+# Globals
+#   ${confirm}: y/n the result of the confirmation
+# Arguments
+#   $1: message to show
+
+function get_confirmation() {
+  unset confirm
+  while [[ "${confirm}" != 'y'  && "${confirm}" != 'n' ]]; do
+    read -p "$1(y/n): " confirm
+  done
+}