and the inspection tables. The sub-module [Shared] in the generated
code is no longer necessary.
Defined [n2i] in [TableInterpreter] (another unsafe cast!).
Used it to implement [nullable], which is now exposed to the user.

and the functor [Symbols] (in [InspectionTableInterpreter]).
This removes the need for generating the types [symbol] and [xsymbol].
The module [SymbolType] in the table back-end disappears.

not work.
Exposed the definition of [symbol] in terms of [terminal] and [nonterminal].
This allows removing this definition from the generated [.mli] file.

This might allow the ocaml compiler to not link these modules when
--inspection is off.