Add zap show version CLI command. This pulls the version/echo canceller in use...

Add zap show version CLI command. This pulls the version/echo canceller in use directly using the ZT_GETVERSION ioctl. (issue #9094 reported by tootai)


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@57943 65c4cc65-6c06-0410-ace0-fbb531ad65f3