initial draft of attendance use case (adding existing resources to collections)

[elf-pavlik]

This PR complements #134 and acts as an example use case

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This change is 

[lanthaler]

let's briefly discuss it in tomorrow's telecon and merge it right after

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Reviewed 1 of 1 files at r1. Review status: all files reviewed at latest revision, 2 unresolved discussions.

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drafts/use-cases/9.adding-existing-resources-to-collections.md, line 9 at r1 (raw file):

As an application user
I want to be able to add events to the list of event I attended

event -> events

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drafts/use-cases/9.adding-existing-resources-to-collections.md, line 63 at r1 (raw file):

In similar way each person can reference collection which lists events this person attended:

--> Similarly, each person can reference a collection which lists the events this person attended:

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Comments from Reviewable

[elf-pavlik]

Review status: 0 of 1 files reviewed at latest revision, 2 unresolved discussions.

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drafts/use-cases/9.adding-existing-resources-to-collections.md, line 9 at r1 (raw file):

Previously, lanthaler (Markus Lanthaler) wrote…

event -> events

Done.

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drafts/use-cases/9.adding-existing-resources-to-collections.md, line 63 at r1 (raw file):

Previously, lanthaler (Markus Lanthaler) wrote…

--> Similarly, each person can reference a collection which lists the events this person attended:

Done.

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Comments from Reviewable

[tpluscode]

Reviewed 1 of 1 files at r2. Review status: all files reviewed at latest revision, 2 unresolved discussions.

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Comments from Reviewable