Implemented property ultra-sugar

Dogfooded in one involved class of the compiler:

package stab.tools.syntaxtree {

public class PropertyDeclarationNode : TypeMemberNode, IInterfaceMember,
IAccessorsOwner {
public PropertyDeclarationNode()
: super(TypeMemberKind.Property) {
}

property TypeReferenceNode Type;
property int NameOffset;
property int NameLength;
property AccessorDeclarationNode GetAccessor;
property AccessorDeclarationNode SetAccessor;
}
}