Long path support #877
Description
React Native for Windows creates apps that can end up with some paths that need to be built that are too long (e.g. C:\users\myname\source\repos\MyAppProject\node_modules\react-native-windows\Microsoft.ReactNative\Generated Files\winrt\Insert.Your.Favorite.Long.Namespace.Here.h ). We see lots of issues where people are creating their project starting in an already pretty deeply-nested folder, and the build fails.