#1087 Add 'Eliminate state invariants' CIF to CIF transformations

• This turned out to be much more subtle than I realized upfront, so it also took a bit more time to get it right.
• Best to review per commit, but read the commit messages as some changes are spread out over multiple commits.
• End-user visible changes:
  • A new 'Eliminate state invariants' CIF to CIF transformation has been added. It comes in three variants: one that eliminates all state invariants, one that only eliminates plant state invariants, and one that only eliminates supervisor state invariants.
• Other changes:
  • Added CifCollectUtils.collectInvariants.
  • Improved SimplifyValues:
    • Made 'dummyInv' field final.
    • JavaDoc improvements for transform(Expression).
    • transform(Expression) is now easier to use; no more null result. It handles completely replaced expressions in the transform method now, rather than callers having to handle it. Updated CIF to mCRL2 transformation for this change.
    • Check preconditions.
  • Improved CifAddressableUtils:
    • Improved/extended JavaDocs/comments.
    • Improved code, using more modern Java concepts.
    • getRefExprs and collectProjs now check for no wrapping expressions.
    • Added new hasProjs method.
  • Added new CifUpdateUtils class.
    • It comes with hasProjectedAddressable and hasTupleAddressable methods.
    • Some methods from ElimIfUpdates have been moved to CifUpdateUtils, to allow reusing them, and also come with these changes:
      • Updated/improved JavaDocs/comments.
      • Comments re-wrapped to 120 characters line length.
      • Added new exception, as can't use one from CIF to CIF transformer.
      • Make sure enough deepcloning is used.
      • Don't support wrapping expressions in addressables.
    • Added new updatesToNewValueExprPerVar method.
  • Added CifValueUtils.hasSubExprSatisfyingPred method.

Closes #1087 (closed)