specify properties for versions

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self-endpoint for version

also link in WP

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specify /api/v3/versions/{id}/projects

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define error responses for versions

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fix errors

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fix C&P example typo

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spelling: That's why

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specify partial visibility of definingProject

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fix table

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specify better suited permissions

- also fix an embarrassing typo ^^

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Merge pull request #2241 from opf/feature/specify_patchable_version

Specify patchable version