Use WebM in copyright notice for consistency

Changes 'The VP8 project' to 'The WebM project', for consistency
with other webmproject.org repositories.

Fixes issue #97.

Change-Id: I37c13ed5fbdb9d334ceef71c6350e9febed9bbba
diff --git a/vpx_mem/vpx_mem.c b/vpx_mem/vpx_mem.c
index ded432a..85b05ab 100644
--- a/vpx_mem/vpx_mem.c
+++ b/vpx_mem/vpx_mem.c
@@ -1,5 +1,5 @@
 /*
- *  Copyright (c) 2010 The VP8 project authors. All Rights Reserved.
+ *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source