Introduce another semantic value stack for Ripper so that
Ripper can manage both Node and Ruby Object separately.
This rearchitectutre of Ripper solves these issues.
Therefore adding test cases for them.

* [Bug 10436] https://bugs.ruby-lang.org/issues/10436
* [Bug 18988] https://bugs.ruby-lang.org/issues/18988
* [Bug 20055] https://bugs.ruby-lang.org/issues/20055

Checked the differences of `Ripper.sexp` for files under `/test/ruby`
are only on test_pattern_matching.rb.
The differences comes from the differences between
`new_hash_pattern_tail` functions between parser and Ripper.
Ripper `new_hash_pattern_tail` didn’t call `assignable` then
`kw_rest_arg` wasn’t marked as local variable.
This is also fixed by this commit.

```
--- a/./tmp/before/test_pattern_matching.rb
+++ b/./tmp/after/test_pattern_matching.rb
@@ -3607,7 +3607,7 @@
                  [:in,
                   [:hshptn, nil, [], [:var_field, [:@ident, “a”, [984, 13]]]],
                   [[:binary,
-                    [:vcall, [:@ident, “a”, [985, 10]]],
+                    [:var_ref, [:@ident, “a”, [985, 10]]],
                     :==,
                     [:hash, nil]]],
                   nil]]],
@@ -3662,7 +3662,7 @@
                  [:in,
                   [:hshptn, nil, [], [:var_field, [:@ident, “a”, [993, 13]]]],
                   [[:binary,
-                    [:vcall, [:@ident, “a”, [994, 10]]],
+                    [:var_ref, [:@ident, “a”, [994, 10]]],
                     :==,
                     [:hash,
                      [:assoclist_from_args,
@@ -3813,7 +3813,7 @@
                    [:command,
                     [:@ident, “raise”, [1022, 10]],
                     [:args_add_block,
-                     [[:vcall, [:@ident, “b”, [1022, 16]]]],
+                     [[:var_ref, [:@ident, “b”, [1022, 16]]]],
                      false]]],
                   [:else, [[:var_ref, [:@kw, “true”, [1024, 10]]]]]]]],
                nil,
@@ -3876,7 +3876,7 @@
                      [:@int, “0”, [1033, 15]]],
                     :“&&“,
                     [:binary,
-                     [:vcall, [:@ident, “b”, [1033, 20]]],
+                     [:var_ref, [:@ident, “b”, [1033, 20]]],
                      :==,
                      [:hash, nil]]]],
                   nil]]],
@@ -3946,7 +3946,7 @@
                      [:@int, “0”, [1042, 15]]],
                     :“&&“,
                     [:binary,
-                     [:vcall, [:@ident, “b”, [1042, 20]]],
+                     [:var_ref, [:@ident, “b”, [1042, 20]]],
                      :==,
                      [:hash,
                       [:assoclist_from_args,
@@ -5206,7 +5206,7 @@
                      [[:assoc_new,
                        [:@label, “c:“, [1352, 22]],
                        [:@int, “0”, [1352, 25]]]]]],
-                   [:vcall, [:@ident, “r”, [1352, 29]]]],
+                   [:var_ref, [:@ident, “r”, [1352, 29]]]],
                   false]]],
                [:binary,
                 [:call,
@@ -5299,7 +5299,7 @@
                       [:assoc_new,
                        [:@label, “c:“, [1367, 34]],
                        [:@int, “0”, [1367, 37]]]]]],
-                   [:vcall, [:@ident, “r”, [1367, 41]]]],
+                   [:var_ref, [:@ident, “r”, [1367, 41]]]],
                   false]]],
                [:binary,
                 [:call,
@@ -5931,7 +5931,7 @@
              [:in,
               [:hshptn, nil, [], [:var_field, [:@ident, “r”, [1533, 11]]]],
               [[:binary,
-                [:vcall, [:@ident, “r”, [1534, 8]]],
+                [:var_ref, [:@ident, “r”, [1534, 8]]],
                 :==,
                 [:hash,
                  [:assoclist_from_args,
```

Introduce Universal Parser mode for the parser.
This commit includes these changes:

* Introduce `UNIVERSAL_PARSER` macro. All of CRuby related functions
  are passed via `struct rb_parser_config_struct` when this macro is enabled.
* Add CI task with 'cppflags=-DUNIVERSAL_PARSER' for ubuntu.

I noticed that some files in rubygems were executable, and I could think
of no reason why they should be.

In general, I think ruby files should never have the executable bit set
unless they include a shebang, so I run the following command over the
whole repo:

```bash
find . -name '*.rb' -type f -executable -exec bash -c 'grep -L "^#!" $1 || chmod -x $1' _ {} \;
```

Currently, parse.y actions are hard to read and write because the code
has double meaning (for core parser and for ripper).  I think that, if
it is easy to write ripper's code shortly and simply, the double meaning
trick is not needed.

For the sake, this change adds a simple DSL for ripper's code.  For
example, in parse.y, we can write:

    /*% ripper: stmts_add(stmts_new, void_stmt) %*/

instead of:

    $$ = dispatch2(stmts_add, dispatch0(stmts_new),
                   dispatch0(void_stmt));

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61952 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@57538 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

g -L frozen_string_literal ext/**/*.rb|xargs ruby -Ka -e'ARGV.each{|fn|puts
fn;open(fn,"r+"){|f|s=f.read.sub(/\A(#!.*\n)?(#.*coding.*\n)?/,"\\&#
frozen_string_literal: false\n");f.rewind;f.write s}}'

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53143 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

* ext/ripper/eventids2.c (token_assoc): reduce size.  unsigned
  short can hold 65535 at least.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48169 b2dd03c8-39d4-4d8f-98ff-823fe69b080e