TW-1715: Add minimized testcase

test/tw-1715.t

@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+. bash_tap_tw.sh
+
+echo "uda.ticketdate.type=date" >> taskrc
+
+# This adds a task with a wrong ticketdate. If rc.dateformat is set, it works as expected.
+task add basetask ticketdate:2015-09-03T08:00:00Z
+
+# For seeing the problem in test output; not needed to make the test fail.
+task export
+
+task export | grep -E '"ticketdate":\s*"20150903T080000Z"'