refactor: stop reexporting transformer from index.js

This won't work for projects that don't have dependency for
`@ngtools/webpack`.

Author: sis0k0

Diff for: index.js

@@ -10,7 +10,6 @@ const {
 
 Object.assign(exports, require("./plugins"));
 Object.assign(exports, require("./host/resolver"));
-Object.assign(exports, require("./transformers/ns-replace-bootstrap"));
 
 exports.getAotEntryModule = function (appDirectory) {
 	verifyEntryModuleDirectory(appDirectory);

Diff for: templates/webpack.angular.js

@@ -3,6 +3,7 @@ const { join, relative, resolve, sep } = require("path");
 const webpack = require("webpack");
 const nsWebpack = require("nativescript-dev-webpack");
 const nativescriptTarget = require("nativescript-dev-webpack/nativescript-target");
+const { nsReplaceBootstrap } = require("nativescript-dev-webpack/transformers/ns-replace-bootstrap");
 const CleanWebpackPlugin = require("clean-webpack-plugin");
 const CopyWebpackPlugin = require("copy-webpack-plugin");
 const { BundleAnalyzerPlugin } = require("webpack-bundle-analyzer");
@@ -51,7 +52,7 @@ module.exports = env => {
 
     const ngCompilerPlugin = new AngularCompilerPlugin({
         hostReplacementPaths: nsWebpack.getResolver([platform, "tns"]),
-        platformTransformers: aot ? [nsWebpack.nsReplaceBootstrap(() => ngCompilerPlugin)] : null,
+        platformTransformers: aot ? [nsReplaceBootstrap(() => ngCompilerPlugin)] : null,
         mainPath: resolve(appPath, entryModule),
         tsConfigPath: join(__dirname, "tsconfig.esm.json"),
         skipCodeGeneration: !aot,

Diff for: transformers/ns-replace-bootstrap.ts

@@ -7,7 +7,7 @@ import {
     insertStarImport,
     ReplaceNodeOperation,
     makeTransform
-} from "@ngtools/webpack/src/transformers"
+} from "@ngtools/webpack/src/transformers";
 import { workaroundResolve } from '@ngtools/webpack/src/compiler_host';
 import { AngularCompilerPlugin } from '@ngtools/webpack';