Allow generic types to be used as function parameter types, e.g. #(x as C<T>)
Allow __iter to accept an object that has a .next method (this is used by for-from)
Add 'send' method to generators, as in the spec.
Allow yield as an assignment or let.
Allow try catch e == obj as well as try catch e as obj.
Rework the way generators are compiled to support yield as an expression, allowing it to receive information from the generator's send method.
Bump version to 0.5.4