Switch to using the dep tool and update all the dependencies

vendor/github.com/stretchr/testify/http/test_response_writer.go

@@ -0,0 +1,49 @@
+package http
+
+import (
+	"net/http"
+)
+
+// TestResponseWriter DEPRECATED: We recommend you use http://golang.org/pkg/net/http/httptest instead.
+type TestResponseWriter struct {
+
+	// StatusCode is the last int written by the call to WriteHeader(int)
+	StatusCode int
+
+	// Output is a string containing the written bytes using the Write([]byte) func.
+	Output string
+
+	// header is the internal storage of the http.Header object
+	header http.Header
+}
+
+// Header DEPRECATED: We recommend you use http://golang.org/pkg/net/http/httptest instead.
+func (rw *TestResponseWriter) Header() http.Header {
+
+	if rw.header == nil {
+		rw.header = make(http.Header)
+	}
+
+	return rw.header
+}
+
+// Write DEPRECATED: We recommend you use http://golang.org/pkg/net/http/httptest instead.
+func (rw *TestResponseWriter) Write(bytes []byte) (int, error) {
+
+	// assume 200 success if no header has been set
+	if rw.StatusCode == 0 {
+		rw.WriteHeader(200)
+	}
+
+	// add these bytes to the output string
+	rw.Output = rw.Output + string(bytes)
+
+	// return normal values
+	return 0, nil
+
+}
+
+// WriteHeader DEPRECATED: We recommend you use http://golang.org/pkg/net/http/httptest instead.
+func (rw *TestResponseWriter) WriteHeader(i int) {
+	rw.StatusCode = i
+}