Fix extra whitespace.

memfile.go

diff --git a/memfile.go b/memfile.go
index 6f4edb4..50f148c 100644
--- a/memfile.go
+++ b/memfile.go
@@ -113,7 +113,6 @@
 	} else {
 		n = len(f.data) - int(f.at)
 	}
-
 	copy(b, f.data[f.at:f.at+int64(n)])
 	atomic.AddInt64(&f.at, int64(n))
 	return