Sage IR node default constructors

Sage IR node default constructors are not useful.

Default constructors and destructors for the SageIII IR nodes (classes whose names begin with "Sg") such as those that compose the abstract syntax tree (AST) are generally not documented in their respective classes because it is not that useful to construct them this way. A better way to construct IR nodes is with the SageBuilder API.

Collaboration diagram for Sage IR node default constructors: