Add parameter --output-filename and store in output_filename

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
CalibratorEvdev: do write calibration results if --output-filename was set

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
CalibratorXorgPrint: do write calibration results if --output-filename was set

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
CalibratorUsbtouchscreen: overridde default file name when setting --output-filename

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
Make all Calibrator* destructors virtual to fix warning

warning was:

main_x11.cpp: In function 'int main(int, char**)':
main_x11.cpp:42:12: warning: deleting object of abstract class type 'Calibrator' which has non-virtual destructor will cause undefined behaviour [-Wdelete-non-virtual-dtor]calibrator/Usbtouchscreen.cpp: In member function 'void CalibratorUsbtouchscreen::read_int_parameter(const char*, int&)':

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
Set up buffer size for max line length only once in calibrator.hh

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