SYSML2_ — Global scope notation

Problem:
Currently, there is no global scope operator specified. This makes it impossible to target an element in the global scope if an element with the same name exists in an intermediate scope.

We should be able to target an element in the global scope, even if an intermediate element has the same name.

Proposed Solution:
Introduce a global scope operator: $::

Example using the global scope notation:

$::'Port Example'::FuelOutPort::temperature