opentracing -> opencensus (#802)

* update vendor directory, add go.opencensus.io

* update imports

* oops

* s/opentracing/opencensus/ & remove prometheus / zipkin stuff & remove old stats

* the dep train rides again

* fix gin build

* deps from last guy

* start in on the agent metrics

* she builds

* remove tags for now, cardinality error is fussing. subscribe instead of register

* update to patched version of opencensus to proceed for now TODO switch to a release

* meh

fix imports

* println debug the bad boys

* lace it with the tags

* update deps again

* fix all inconsistent cardinality errors

* add our own logger

* fix init

* fix oom measure

* remove bugged removal code

* fix s3 measures

* fix prom handler nil

vendor/github.com/aws/aws-sdk-go/internal/sdkrand/locked_source.go

@@ -0,0 +1,29 @@
+package sdkrand
+
+import (
+	"math/rand"
+	"sync"
+	"time"
+)
+
+// lockedSource is a thread-safe implementation of rand.Source
+type lockedSource struct {
+	lk  sync.Mutex
+	src rand.Source
+}
+
+func (r *lockedSource) Int63() (n int64) {
+	r.lk.Lock()
+	n = r.src.Int63()
+	r.lk.Unlock()
+	return
+}
+
+func (r *lockedSource) Seed(seed int64) {
+	r.lk.Lock()
+	r.src.Seed(seed)
+	r.lk.Unlock()
+}
+
+// SeededRand is a new RNG using a thread safe implementation of rand.Source
+var SeededRand = rand.New(&lockedSource{src: rand.NewSource(time.Now().UnixNano())})