allow falling back to amazon's ETag for the file when checking md5. This will help us correctly set the md5 on manually uploaded files. It does however fall apart if amazon ever changes the ETag, which their docs warn they reserve the right to.
allow falling back to amazon's ETag for the file when checking md5. This will help us correctly set the md5 on manually uploaded files. It does however fall apart if amazon ever changes the ETag, which their docs warn they reserve the right to.


svn commit r68747

nburka/site,silverorange/site,silverorange/site,nburka/site