vendor: update all dependencies except Azure SDK

The Azure SDK doesn't support Go 1.5 anymore. We can't upgrade it until
Go 1.8 comes out.

vendor/github.com/rcrowley/go-metrics/gauge.go

@@ -44,7 +44,6 @@ func NewFunctionalGauge(f func() int64) Gauge {
 	return &FunctionalGauge{value: f}
 }
 
-
 // NewRegisteredFunctionalGauge constructs and registers a new StandardGauge.
 func NewRegisteredFunctionalGauge(name string, r Registry, f func() int64) Gauge {
 	c := NewFunctionalGauge(f)
@@ -101,6 +100,7 @@ func (g *StandardGauge) Update(v int64) {
 func (g *StandardGauge) Value() int64 {
 	return atomic.LoadInt64(&g.value)
 }
+
 // FunctionalGauge returns value from given function
 type FunctionalGauge struct {
 	value func() int64
@@ -117,4 +117,4 @@ func (g FunctionalGauge) Snapshot() Gauge { return GaugeSnapshot(g.Value()) }
 // Update panics.
 func (FunctionalGauge) Update(int64) {
 	panic("Update called on a FunctionalGauge")
-}
+}