add in Go case insensitive stream from bramp

doc/case-insensitive-lexing.md

@@ -68,4 +68,9 @@ Then, when creating the character stream to parse from, we need a custom class t
 CharStream s = CharStreams.fromPath(Paths.get('test.sql'));
 CaseChangingCharStream upper = new CaseChangingCharStream(s, true);
 Lexer lexer = new SomeSQLLexer(upper);
-```
+```
+
+Here are implementations of `CaseChangingCharStream` in various target languages:
+
+* [Java](https://github.com/parrt/antlr4/blob/case-insensitivity-doc/doc/resources/CaseChangingCharStream.java)
+* 

runtime/Go/antlr/case_changing_stream_test.go

@@ -1,32 +0,0 @@
-package antlr
-
-import (
-	"github.com/kylelemons/godebug/pretty"
-	"testing"
-)
-
-func TestCaseChangingStream(t *testing.T) {
-	tests := []struct {
-		input string
-		upper bool
-		want  []int
-	}{
-		{"abcd", true, []int{'A', 'B', 'C', 'D', TokenEOF}},
-		{"ABCD", true, []int{'A', 'B', 'C', 'D', TokenEOF}},
-		{"abcd", false, []int{'a', 'b', 'c', 'd', TokenEOF}},
-		{"ABCD", false, []int{'a', 'b', 'c', 'd', TokenEOF}},
-		{"", false, []int{TokenEOF}},
-	}
-
-	for _, test := range tests {
-		var got []int
-		is := NewCaseChangingStream(NewInputStream(test.input), test.upper)
-		for i := 1; i <= is.Size()+1; i++ {
-			got = append(got, is.LA(i))
-		}
-
-		if diff := pretty.Compare(test.want, got); diff != "" {
-			t.Errorf("NewCaseChangingStream(%q, %v) diff: (-got +want)\n%s", test.input, test.upper, diff)
-		}
-	}
-}