[Feature request] Add ability to call the connection in labels by using element specialization info (in reference prefixes)

[startsevsa]

At this moment when using a reference prefix <relationship>: if having multiple connections of the same type and direction Archi references "the first connected relationship". And the order of connections, which determines the "first" connection is not clear to the user (it depends on the connections creation order and which of connections are visible on the view).

The suggestion is to add an extension to a reference prefix to point to a connection of the specific specialization.
Ideally will be ability to call a connection by it's name (but specialization is acceptable :) ).

The main idea is to move from the visual representation to a real modeling of architecture.

The variant of syntax:
$aggregation.specialization{Initial plateau}:target{name}

Example of use - defining the creation, modification and deletion plaeau for the current element.

Here the goal is to show the info even without visualising the connections:

1. for an example above
   
2. the extended example, that shows the stages of architecture implementation