Fixes issue #1496; replaces slower byte-by-byte MD5 hash calculation with a faster call.  Also makes ImageBundleBuilder a little  faster by not having to read each image twice.

Patch by: tobyr, scottb, mmendez
Review by: rdayal, mmendez, scottb

git-svn-id: https://google-web-toolkit.googlecode.com/svn/trunk@1306 8db76d5a-ed1c-0410-87a9-c151d255dfc7
4 files changed