Update Zipkin.thrift

[yurishkuro]

Our zipkin.thrift is out of date and missing some fields like 128bit trace ID and ipv6.

https://github.com/uber/jaeger/pull/334#discussion_r133116969

[pavolloffay]

@black-adder could you please re-open? And close once thrift-gen is updated.

(It was automatically closed)