Use a vendor directory for repeatable builds - fixes #816

This is using godep to manage the vendor directory.

vendor/github.com/ncw/swift/watchdog_reader.go

@@ -0,0 +1,34 @@
+package swift
+
+import (
+	"io"
+	"time"
+)
+
+// An io.Reader which resets a watchdog timer whenever data is read
+type watchdogReader struct {
+	timeout time.Duration
+	reader  io.Reader
+	timer   *time.Timer
+}
+
+// Returns a new reader which will kick the watchdog timer whenever data is read
+func newWatchdogReader(reader io.Reader, timeout time.Duration, timer *time.Timer) *watchdogReader {
+	return &watchdogReader{
+		timeout: timeout,
+		reader:  reader,
+		timer:   timer,
+	}
+}
+
+// Read reads up to len(p) bytes into p
+func (t *watchdogReader) Read(p []byte) (n int, err error) {
+	// FIXME limit the amount of data read in one chunk so as to not exceed the timeout?
+	resetTimer(t.timer, t.timeout)
+	n, err = t.reader.Read(p)
+	resetTimer(t.timer, t.timeout)
+	return
+}
+
+// Check it satisfies the interface
+var _ io.Reader = &watchdogReader{}