Reraise boto/httplib errors as IOErrors
The s3boto backend currently lets exceptions from the connection to s3 propagate. It seems like the correct behavior would be to catch these and reraise them as IOErrors, to more closely emulate the behavior of (say) the filesystem backend.
Affected exceptions would include:
There are probably other exceptions which it might also make sense to catch and reraise as IOError; these are just the ones I've run into.