caller and child arguments of inh

[Jesper Mattsson]

When declaring an inherited attibute, it is not clear that you are not allowed to have arguments to it named "child" or "caller", and the resulting error from the Java compiler requires understanding the generated code to figure out what's wrong.

I suggest switching "child" and "caller" to something less likely to be used, like "_child" and "_caller".

[Jesper Öqvist]

Rename hidden inherited attribute parameters

Renamed the hidden inherited attribute parameters "child" and "caller" to "_childNode" and "_callerNode" in order to reduce the likelyhood of name clashes with the formal attribute parameters. The "_childNode" and "_callerNode" names should be less common as parameter names.

fixes #236 (bitbucket)

→ <<cset 3da42d51a068>>