Added a test of evaluation order of the actuals.
Merge pull request #123 from vasslitvinov/add-test-of-order-of-evaluation-of-actuals

Added a test of evaluation order of the actuals.

This test documents the current state of affairs.
It does not specify the party line.

I did not see in the spec the definition of the order
in which the actuals of a function call are evaluated.
One might want to define the evaluation order to be the order
in which the actuals appear in the call.
However this is not how it is implemented right now.
In particular, in this call:

  someFunction(someVariable, someSideEffectingFunction())

someSideEffectingFunction() will be called first, before
someVariable's value is read.

One benefit of doing it this way is passing variables to functions
directly. I.e. we avoid creating argument temps in the caller.