Add more tests for keys with escaped characters

[mosiac1]

Tests are currently failing.

From the SigV4 spec, the path included in the Canonical Request string should have its segments URI encoded.

Both the Java AWS SDK and the AWS CLI will encode the path before sending the request. For example, for the key a=1 in bucket foo the request path would be /foo/a%3D1. This is both the path used in the Canonical Request (for SigV4) and the path of the actual HTTP request.

Playing around with modifying the HTTP path of signed requests I found that Ceph S3 will consider the signature valid even if the path is not encoded. For the example above, Ceph treats /foo/a%3D1 and /foo/a=1 as equivalent.

I think aws-proxy should behave the same, decoding the path once and re-encoding when computing the Canonical Request strings.

Looks like Jetty doesn't do this by default, which does make sense as most reserved URI characters are allows in paths.

[mosiac1]

Closing, this PR was for documentation purposes, I am not sure we should support this encoding/decoding behaviour as a proxy.