Add benchmarking module

[chuwy]

For reference snowplow/enrich#370

[chuwy]

#107 is the first target for benchmarking.

[chuwy]

Another good candidate for micro-benchmarks - atomic can be rewritten as toJsonMap - Set("contexts", "unstruct_event", "derived_contexts"). Wondering if this version will be more performant.

[chuwy]

Third one - ordered can be implemented as:

def ordered: Iterable[(String, Json)] =
  this.asJsonObject.toIterable

Not 100% sure that implementation is identical (and type is certainly not), but wondering if we can add it as an option.

[benjben]

Thanks for all the details @chuwy !

[benjben]

atomic without the -- Set():

[info] Result "com.snowplowanalytics.snowplow.analytics.scalasdk.benchmark.BenchmarkAnalyticsSDK.atomic":
[info]   0.366 ±(99.9%) 0.022 us/op [Average]
[info]   (min, avg, max) = (0.319, 0.366, 0.434), stdev = 0.025
[info]   CI (99.9%): [0.345, 0.388] (assumes normal distribution)
[info] # Run complete. Total time: 00:08:4

With it:

[info] Result "com.snowplowanalytics.snowplow.analytics.scalasdk.benchmark.BenchmarkAnalyticsSDK.atomic":
[info]   0.589 ±(99.9%) 0.012 us/op [Average]
[info]   (min, avg, max) = (0.566, 0.589, 0.616), stdev = 0.014
[info]   CI (99.9%): [0.577, 0.601] (assumes normal distribution)
[info] # Run complete. Total time: 00:08:42

Surprisingly enough the first one is more performant