maint: update todo

* TODO: Remove fixed items.

TODO

@@ -48,9 +48,6 @@ Get rid of it.  The original idea is nice, but actually it makes
 the code harder to follow, and uselessly different from the other
 skeletons.
 
-** Variable names.
-What should we name `variant' and `lex_symbol'?
-
 ** Get rid of fake #lines [Bison: ...]
 Possibly as simple as checking whether the column number is nonnegative.
 
@@ -77,9 +74,6 @@ since it is no longer bound to a particular parser, it's just a
 ** Rename LR0.cc
 as lr0.cc, why upper case?
 
-** bench several bisons.
-Enhance bench.pl with %b to run different bisons.
-
 * Various
 ** YYERRCODE
 Defined to 256, but not used, not documented.  Probably the token
@@ -143,12 +137,6 @@ really possible?  The test suite does not exercise this case.
 This shows that it would be interesting to manage to install skeleton
 coverage analysis to the test suite.
 
-** Table definitions
-It should be very easy to factor the definition of the various tables,
-including the separation bw declaration and definition.  See for
-instance b4_table_define in lalr1.cc.  This way, we could even factor
-C vs. C++ definitions.
-
 * From lalr1.cc to yacc.c
 ** Single stack
 Merging the three stacks in lalr1.cc simplified the code, prompted for
@@ -274,9 +262,6 @@ Paul notes:
         tokens, either via escapes (e.g., "x\0y") or via a NUL byte in
         the source code.  This should get fixed.
 
-* --graph
-Show reductions.
-
 * Broken options ?
 ** %token-table
 ** Skeleton strategy