Golang opentelemetry-go draft API (incomplete) (#9)

* Work in progress from https://github.com/lightstep/opentelemetry-golang-prototype

* Renames

* Rename

* Finish rename

* Rename packages

* README

api/stats/stats.go

@@ -0,0 +1,50 @@
+package stats
+
+import (
+	"context"
+
+	"github.com/open-telemetry/opentelemetry-go/api/core"
+	"github.com/open-telemetry/opentelemetry-go/api/scope"
+	"github.com/open-telemetry/opentelemetry-go/exporter/observer"
+)
+
+type (
+	Interface interface {
+		Record(ctx context.Context, m ...core.Measurement)
+		RecordSingle(ctx context.Context, m core.Measurement)
+	}
+
+	Recorder struct {
+		core.ScopeID
+	}
+)
+
+func With(scope scope.Scope) Recorder {
+	return Recorder{scope.ScopeID()}
+}
+
+func Record(ctx context.Context, m ...core.Measurement) {
+	With(scope.Active(ctx)).Record(ctx, m...)
+}
+
+func RecordSingle(ctx context.Context, m core.Measurement) {
+	With(scope.Active(ctx)).RecordSingle(ctx, m)
+}
+
+func (r Recorder) Record(ctx context.Context, m ...core.Measurement) {
+	observer.Record(observer.Event{
+		Type:    observer.RECORD_STATS,
+		Scope:   r.ScopeID,
+		Context: ctx,
+		Stats:   m,
+	})
+}
+
+func (r Recorder) RecordSingle(ctx context.Context, m core.Measurement) {
+	observer.Record(observer.Event{
+		Type:    observer.RECORD_STATS,
+		Scope:   r.ScopeID,
+		Context: ctx,
+		Stat:    m,
+	})
+}