chore: merge release into master (#860)

* release: cut the 0.21.0 release

* fix: add support for ts files on test command when `--bundle` is provided (#848)

Rel to:
NativeScript/nativescript-cli#4477
NativeScript/nativescript-cli#1798

* fix: use correct slashes on windows (#851)

* fix: fix "ERROR in Must have a source file to refactor." error from ngCompilerPlugin on `test` command (#859)

Author: Fatme

templates/webpack.angular.js

@@ -90,7 +90,7 @@ module.exports = env => {
     const ngCompilerPlugin = new AngularCompilerPlugin({
         hostReplacementPaths: nsWebpack.getResolver([platform, "tns"]),
         platformTransformers: ngCompilerTransformers.map(t => t(() => ngCompilerPlugin, resolve(appFullPath, entryModule))),
-        mainPath: resolve(appPath, entryModule),
+        mainPath: join(appFullPath, entryModule),
         tsConfigPath: join(__dirname, tsConfigName),
         skipCodeGeneration: !aot,
         sourceMap: !!sourceMap,