Changes

#119 (Nov 20, 2017, 4:14:13 PM)

1. Use term SpanContext for inject/extract, explain span.kind tag — Pavol Loffay / detail

#109 (Nov 13, 2017, 3:54:10 PM)

1. next rev of opentracing spec — Steve Fontes / detail
2. updates from some review comments — Steve Fontes / detail
3. Clarification of @Traced(false) — Steve Fontes / detail
4. Update README — Steve Fontes / detail
5. Make README consistent with spec — Steve Fontes / detail
6. Make README consistent with spec — Steve Fontes / detail