fix go evt problem

Go vet reported a problem with the interface of WriteTo returning an
int.

  Line 13: method WriteTo(stream io.Writer) (int, error)
        should have signature WriteTo(io.Writer) (int64, error)

To fix that problem, the interface was changed to return io.WriterTo,
which uses int64 for return values.

1 files changed, 3 insertions, 2 deletions

diff --git a/pem_marshal.go b/pem_marshal.go
index 14b3bd4..54ce1e0 100644
--- a/pem_marshal.go
+++ b/pem_marshal.go
@@ -10,6 +10,7 @@ type (
 
 // This function writes the marshalled pem block to a writer and returns the
 // number of written bytes and eventual errors.
-func (b marshalledPemBlock) WriteTo(stream io.Writer) (int, error) {
-  return stream.Write(b)
+func (b marshalledPemBlock) WriteTo(stream io.Writer) (int64, error) {
+  numBytes, err := stream.Write(b)
+  return int64(numBytes), err
 }