xinput_calibrator_pointercal2.sh: Add new script to make calibration permanent

* using new parameter --output-filename
* support multiple devices
* by using files xorg.conf.d no need to perform script at startup
* when using this script together with udev/systemd it waits until
  xinput_calibrator detects device (tested)

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>