Implement recursive type and function declaration

[Jegp]

When defining objects it should be allowed to reference the same object and when defining functions the function body should be able to reference the same function.

def Object(a as Object)

def function(a as Number) = { if (a < 10) function(a + 1) }

However the last option could lead to infinite loops:

def function() = function()

So we either allow everything, invent some recursion-discovery mechanism or simple disallow loops in functions for now..