Use hex checsum for hash key instead of raw

To make it easy to debug and support, changing cache keys to use hex checksum instead of raw checksum

[Paul Lindner, 2010-06-18 23:31:50]

Seems okay.  I'd be happier if we had a better toHex() routine that used a
lookup table and a fixed char array rather than a stringbuilder..  If you commit
this patch I'll fix the latter.

lots of whitespace only changes..  thanks for adding @Override

[zhoresh, 2010-06-18 23:40:28]

It all thanks to Eclipse for fixing spaces, overrides etc. :)
Committed, thanks for looking into improving the hex convert.

On Fri, Jun 18, 2010 at 4:31 PM, <lindner@inuus.com> wrote:

> Seems okay.  I'd be happier if we had a better toHex() routine that used
> a lookup table and a fixed char array rather than a stringbuilder..  If
> you commit this patch I'll fix the latter.
>
> lots of whitespace only changes..  thanks for adding @Override
>
>
> http://codereview.appspot.com/1723043/show
>