Remove inherintence of supervisory kind for invariants.

Kindless invariants for synthesis were deprecated on the 11th of October 2015. We should no longer support it.

Synthesizing the following specification:

plant A:
  disc int[0..3] X = 3;
  location:
    initial; marked;
end

requirement R:
  location:
    initial; marked;
    invariant A.X != 2;
end

Gives the following warning.

WARNING: File "issue.cif": Semantic warning at line 10, column 19: Invariant does not specify a supervisory kind and thus implicitly inherits supervisory kind "requirement" from automaton "R". This is deprecated. Please explicitly specify the kind before the "invariant" keyword.

Edited Jul 06, 2021 by Ferdie Reijnen