Asset.clone: Preserve the url of the original asset instead of making one up (now that multiple assets can share the same url).
Asset.clone: Preserve the url of the original asset instead of making one up (now that multiple assets can share the same url).

jscinoz/assetgraph,papandreou/assetgraph,assetgraph/assetgraph,papandreou/assetgraph,jscinoz/assetgraph,jscinoz/assetgraph,papandreou/assetgraph,slang800/assetgraph,slang800/assetgraph