Update changelog
caching the zip manifests Fixes #154

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extra : rebase_source : 0f32792e01b6a1b746a1e07ffa4d7a85eeda1595
Must add zipinfo as a property

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extra : rebase_source : 2ae5fa38bd5c9d37b44a010879f2b3a4867c0ee4
Summarize zip_manifest cache changes.

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extra : rebase_source : b4dc90d0244a83083a299600eccce50446ad5846