Fixed Issue #15, updated ED link, see https://github.com/sysapps/telephony/issues/15
Fixed Issue #3, scope and use cases, plus references. See https://github.com/sysapps/telephony/issues/3
Fixed issue #4,added dialEmergency() method, see https://github.com/sysapps/telephony/issues/4
Fixed issue#7, added startTone() and stopTone() for long press DTMF support, see https://github.com/sysapps/telephony/issues/7