Fix mime test.

* mailbox/mime.c (mu_mime_get_part): Fix the end limit for the
part's abridgement.
* mailbox/streamref.c (_streamref_seek): Fix ESPIPE condition.

@@ -895,7 +895,7 @@ mu_mime_get_part (mu_mime_t mime, size_t part, mu_message_t *msg)
 	      ret = mu_streamref_create_abridged (&stream, mime->stream,
 						  mime_part->offset,
 						  mime_part->offset +
-						     mime_part->len);
+						    mime_part->len - 1);
 	      if (ret == 0)
 		{
 		  mu_stream_set_flags (stream,

@@ -169,7 +169,7 @@ _streamref_seek (struct _mu_stream *str, mu_off_t off, mu_off_t *ppos)
       size -= sp->start;
     }
   
-  if (off < 0 || off >= size)
+  if (off < 0 || off > size)
     return sp->stream.last_err = ESPIPE;
   rc = mu_stream_seek (sp->transport, sp->start + off, MU_SEEK_SET,
 		       &sp->offset);