While we might never be able to have 100% of our code strict, we can at
the very least do it for all of our tests. This ensures that our tests
are using our API with the types as intended by the test author, and not
silently be cast to what our API requires.
Calculation engine was resolving every function by first resolving its arguments
including IFs, this was causing significant over evaluation when IFs were used
as it meant for every case to be evaluated.
Introduce elements to identify ifs and enable better branch resolution
(pruning). We tag parsed tokens to associate a branch identifier to them.
Closes#844