d: change the return value of yylex from int to TokenKind

* data/skeletons/lalr1.d: Change the return value.
* examples/d/calc/calc.y, examples/d/simple/calc.y: Adjust.
* tests/scanner.at: Adjust.
* tests/calc.at (_AT_DATA_CALC_Y(d)): New, extracted from...
(_AT_DATA_CALC_Y(c)): here.
The two grammars have been sufficiently different to be separated.
Still trying to be them together results in a maintenance burden.  For
the same reason, instead of specifying the results for D and for the
rest, compute the expected results with D from the regular case.

TODO

@@ -249,21 +249,14 @@ are.  Keep the same variable names.  If you change the wording in one place,
 do it in the others too.  In other words: make sure to keep the
 maintenance *simple* by avoiding any gratuitous difference.
 
-** Change the return value of yylex
-Historically people were allowed to return any int from the scanner (which
-is convenient and allows `return '+'` from the scanner).  Akim tends to see
-this as an error, we should restrict the return values to TokenKind (not to
-be confused with SymbolKind).
-
-In the case of D, without the history, we have the choice to support or not
-`int`.  If we want to _keep_ `int`, is there a way, say via introspection,
-to support both signatures of yylex?  If we don't keep `int`, just move to
-TokenKind.
-
 ** Documentation
 Write documentation about D support in doc/bison.texi.  Imitate the Java
 documentation.  You should be more succinct IMHO.
 
+** yyerrok
+It appears that neither Java nor D support yyerrok currently.  It does not
+need to be named this way...
+
 ** Complete Symbols
 The current interface from the scanner to the parser is somewhat clumsy: the
 token kind is returned by yylex, but the value and location are stored in