Pulled the class out of main.cpp, made a header to go along with it, externed globals in headers to make them accessible to button code. Added button code to send an advert on double press. Refactored ini files to prevent linker errors.
* BasChatMesh: new onContactRequest(), for PAYLOAD_TYPE_REQ handling.
* companion, repeater and room_server: now with basic 'plumbing' to handle REQ_TYPE_GET_TELEMETRY_DATA (0x03).
* dependency: added CayenneLPP to libdeps
* all target.* modules now with a stub 'sensors' object.