feature: refactor api parse to g4 (#365)

* feature: refactor api parse to g4

* new g4 parser

* add CHANGE_LOG.MD

* refactor

* fix byte bug

* refactor

* optimized

* optimized

* revert

* update readme.md

* update readme.md

* update readme.md

* update readme.md

* remove no need

* fix java gen

* add upgrade

* resolve confilits

Co-authored-by: anqiansong <anqiansong@xiaoheiban.cn>

tools/goctl/api/parser/g4/test/grammar_test.go

@@ -0,0 +1,25 @@
+package test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var files = []string{
+	"example",
+	"empty",
+	"syntax",
+	"info",
+	"types",
+	"service",
+}
+
+func TestGrammar(t *testing.T) {
+	for _, file := range files {
+		t.Run(file, func(t *testing.T) {
+			_, err := parser.Parse("./apis/" + file + ".api")
+			assert.Nil(t, err)
+		})
+	}
+}