Change to allow multiple FLOW_CONTEXT (#170)

[l-ohlen-ericsson]

Applicable Issues

Change to allow multiple FLOW_CONTEXT (#170)

Description of the Change

Changed the FLOW CONTEXT link type to allow multiple

Alternate Designs

Not considered

Benefits

Makes it possible to associate an Eiffel event with multiple flows

Possible Drawbacks

Non identified

Sign-off

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Signed-off-by: Lars Ohlén, lars.x.ohlen@ericsson.com

[d-stahl-ericsson]

Version stepping is also required. I would argue that this constitutes a minor version change, e.g. 1.0.0 -> 1.1.0. It shouldn't be major, because a client expecting a 1.0.0 format and getting multiple FLOW_CONTEXT will still be able to parse it and get the same amount of information as before (but miss out on potential additional information).

One example of how to document version stepping can be found in the TERC event:

## Version History
| Version   | Introduced in                                          | Changes                                 |
| --------- | ------------------------------------------------------ | --------------------------------------- |
| 2.0.0     | Current version.                                       | Changed syntax of data.batches.recipes.constraints from an uncontrolled object to a list of key-value pairs to comply with design guidelines. |
| 1.0.0     | [edition-bordeaux](../../../tree/edition-bordeaux)     | Initial version.                        |

Following this change, that would then become

## Version History
| Version   | Introduced in                                          | Changes                                 |
| --------- | ------------------------------------------------------ | --------------------------------------- |
| 2.1.0     | Current version.                                       | Changed FLOW_CONTEXT link type to allow multiple links. |
| 2.0.0     |                                                        | Changed syntax of data.batches.recipes.constraints from an uncontrolled object to a list of key-value pairs to comply with design guidelines. |
| 1.0.0     | [edition-bordeaux](../../../tree/edition-bordeaux)     | Initial version.                        |

[d-stahl-ericsson]

Superceded by #179