[Waterken-server] Multiple return types

[Sandro M. <naa...@gm...>]

C# supports a number of additional side-effects to method invocation
than Java. The following method:

  string foo(string input, int param2) { ... }

is implicitly:

  string foo(in int input, in int param2) { ... }

The other variants are:

  string foo(ref int input, out int param2) { ... }

"ref" is used to pass parameters by reference, ie. setting a ref
parameter induces the local variable in the caller to be modified.

"out" is similar to "ref", except that "out" parameters can be used
with uninitialized variables in the caller, and they must be
initialized by the called function ("foo" in this case).

These semantics are difficult to support in a distributed context, but
assuming it's worthwhile: these are "pass by reference" semantics,
which implies that we must pass in a Link which is the "setter" for
these variables. Any thoughts Tyler?

Sandro