Removes one-way tracing example (#155)
Removes one-way tracing example (#155)

This was never implememented consistently. Also, this document is really
out-of-date. Less content is less to convert.

See https://github.com/openzipkin/brave/pull/1169
openzipkin/openzipkin.github.io,openzipkin/openzipkin.github.io,openzipkin/openzipkin.github.io