Dependency update

Godeps/_workspace/src/github.com/juju/ratelimit/LICENSE

@@ -1,5 +1,8 @@
-This package contains an efficient token-bucket-based rate limiter.
-Copyright (C) 2015 Canonical Ltd.
+All files in this repository are licensed as follows. If you contribute
+to this repository, it is assumed that you license your contribution
+under the same license unless you state otherwise.
+
+All files Copyright (C) 2015 Canonical Ltd. unless otherwise specified in the file.
 
 This software is licensed under the LGPLv3, included below.
 

Godeps/_workspace/src/github.com/juju/ratelimit/ratelimit.go

@@ -7,6 +7,7 @@
 package ratelimit
 
 import (
+	"math"
 	"strconv"
 	"sync"
 	"time"
@@ -55,7 +56,7 @@ func NewBucketWithRate(rate float64, capacity int64) *Bucket {
 			continue
 		}
 		tb := NewBucketWithQuantum(fillInterval, capacity, quantum)
-		if diff := abs(tb.Rate() - rate); diff/rate <= rateMargin {
+		if diff := math.Abs(tb.Rate() - rate); diff/rate <= rateMargin {
 			return tb
 		}
 	}
@@ -217,10 +218,3 @@ func (tb *Bucket) adjust(now time.Time) (currentTick int64) {
 	tb.availTick = currentTick
 	return
 }
-
-func abs(f float64) float64 {
-	if f < 0 {
-		return -f
-	}
-	return f
-}