Kleene replacement erroneous for a few cases about domemtech.trash HOT 1 OPEN

I've rewritten the code, greatly simplifying it. The overall transformation is correct, which is:

// Left recursion:
// Convert A -> A beta1 | A beta2 | ... | alpha1 | alpha2 | ... ;
// into A ->  (alpha1 | alpha2 | ... ) (beta1 | beta2 | ...)*
//
// Right recursion:
// Convert A -> beta1 A | beta2 A | ... | alpha1 | alpha2 | ... ;
// into A ->   (beta1 | beta2 | ...)* (alpha1 | alpha2 | ... )

However, the prior implementation tried to construct a valid tree from scratch. This is extremely hard to do, and required over-the-top verbose code. Instead, the solution is to just construct a string for the collection of alpha and beta symbols for the new rule, and insert that into the parse tree for the code. It does not matter that the parse tree is not strictly an Antlr4 parse tree--it get reserialized on output.

from domemtech.trash.