analysis/app: show median in addition to mean result
analysis/app: show median in addition to mean result

Change-Id: I405ff8d89593365b0e27925e7640bee35c723682
Reviewed-on: https://go-review.googlesource.com/37158
Run-TryBot: Quentin Smith <d6b8e48afb2534b213e391cab43016505747a234@golang.org>
TryBot-Result: Gobot Gobot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Russ Cox <5ad239cb8a44f659eaaee0aa1ea5b94947abe557@golang.org>

golang/perf,golang/perf