Improve support of operators and their properties

[pjljvandelaar]

Currently, we have to make almost identical patterns since we can't generalize over operators.
E.g. almost identical pattern distribution over if branches for + and & operators.

Furthermore, many operators have properties like idempotent, commutative, and associative.
So why do I have to specify both $S_X+0 and 0+$S_X for the + operator?

Note that since operators can be overloaded the properties that hold can change:
multiplication for number is commutative, and thus holds a * b = b * a
Yet, this is not true for matrices: matrix multiplication is not commutative!

[pjljvandelaar]

Generalization over operators is blocked since libadalang doesn't support it (yet).