vendor: pull in github.com/ncw/swift latest to fix reauth on big files

vendor/github.com/ncw/swift/compatibility_1_6.go

@@ -0,0 +1,21 @@
+// +build go1.6
+
+package swift
+
+import (
+	"net/http"
+	"time"
+)
+
+const IS_AT_LEAST_GO_16 = true
+
+func SetExpectContinueTimeout(tr *http.Transport, t time.Duration) {
+	tr.ExpectContinueTimeout = t
+}
+
+func AddExpectAndTransferEncoding(req *http.Request, hasContentLength bool) {
+	req.Header.Add("Expect", "100-continue")
+	if !hasContentLength {
+		req.TransferEncoding = []string{"chunked"}
+	}
+}