Refactor web.add_trace_id_header()

It's bad to send to add_trace_id_header() and headers, cause thy
may contain potential issues, which can be potential security issues.

Intead of that we are adding web.get_trace_id_header() that will
just reutrn dictionray with race info.

Change-Id: I6117979f95a875c27b0698eb051ff50d8e62bd28