Export visitor helpers

Author: leebyron

src/index.js

@@ -87,6 +87,8 @@ export {
 
   // Visit
   visit,
+  visitInParallel,
+  visitWithTypeInfo,
   Kind,
   BREAK,
 } from './language';

src/language/index.js

@@ -14,4 +14,4 @@ export { lex } from './lexer';
 export { parse, parseValue } from './parser';
 export { print } from './printer';
 export { Source } from './source';
-export { visit, BREAK } from './visitor';
+export { visit, visitInParallel, visitWithTypeInfo, BREAK } from './visitor';