Switch to new vendor directory layout

Fixes #113

Signed-off-by: Marcos Lilljedahl <marcosnils@gmail.com>

vendor/github.com/docker/go-units/duration.go

@@ -0,0 +1,33 @@
+// Package units provides helper function to parse and print size and time units
+// in human-readable format.
+package units
+
+import (
+	"fmt"
+	"time"
+)
+
+// HumanDuration returns a human-readable approximation of a duration
+// (eg. "About a minute", "4 hours ago", etc.).
+func HumanDuration(d time.Duration) string {
+	if seconds := int(d.Seconds()); seconds < 1 {
+		return "Less than a second"
+	} else if seconds < 60 {
+		return fmt.Sprintf("%d seconds", seconds)
+	} else if minutes := int(d.Minutes()); minutes == 1 {
+		return "About a minute"
+	} else if minutes < 60 {
+		return fmt.Sprintf("%d minutes", minutes)
+	} else if hours := int(d.Hours()); hours == 1 {
+		return "About an hour"
+	} else if hours < 48 {
+		return fmt.Sprintf("%d hours", hours)
+	} else if hours < 24*7*2 {
+		return fmt.Sprintf("%d days", hours/24)
+	} else if hours < 24*30*3 {
+		return fmt.Sprintf("%d weeks", hours/24/7)
+	} else if hours < 24*365*2 {
+		return fmt.Sprintf("%d months", hours/24/30)
+	}
+	return fmt.Sprintf("%d years", int(d.Hours())/24/365)
+}