FreeSWITCH-FS-7447

Merge pull request #332 in FS/freeswitch from feature/FS-7783-play_and_get_digits-capture-invalid to master

* commit 'eed386bc8d843d01cda4c0ab99382aa3c49f41c5':
  FS-7783 Add channel variable for capturing DTMF input when using play_and_get_digits when the response does not match