Updated release notes.
Improved 'copy' command examples.
Use sparse fingerprints, e.g. 'dynamic:MD5' was always using SHA256 and not the specified hash algorithm.

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branch : v0.4
Merged.
Bumped version.

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branch : v0.4
Updated README with 0.4.2 release notes.

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branch : v0.4
Merged from v0.4.
Merged.
Improved release note.

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branch : v0.4
Added tag v0.4.2 for changeset 948cbb8b3b8d

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branch : v0.4
Merged.