Changed target version to deal with common ? operator error

docs/assets/js/search.json

docs/index.html

docs/interfaces/_types_d_.addmessage.html

docs/interfaces/_types_d_.basemessage.html

docs/interfaces/_types_d_.connectevents.html

docs/interfaces/_types_d_.connectoptions.html

docs/interfaces/_types_d_.deletemessage.html

docs/interfaces/_types_d_.device.html

docs/interfaces/_types_d_.deviceerror.html

docs/interfaces/_types_d_.encodeargs.html

docs/interfaces/_types_d_.errormessage.html

docs/interfaces/_types_d_.getmessage.html

docs/interfaces/_types_d_.initresult.html

docs/interfaces/_types_d_.mqttrequest.html

docs/interfaces/_types_d_.notifymessage.html

docs/interfaces/_types_d_.operatemessage.html

docs/interfaces/_types_d_.operateoptions.html

docs/interfaces/_types_d_.protocol.html

docs/interfaces/_types_d_.protocolargs.html

docs/interfaces/_types_d_.protocolevents.html