Fixing the packager infinite loop on Windows

Summary: The issue here facebook/react-native#2787

The root path '/' dosn't match windows root path
Closes facebook/react-native#2789

Reviewed By: @​svcscm

Differential Revision: D2452718

Pulled By: @martinbigio

react-packager/src/DependencyResolver/DependencyGraph/ResolutionRequest.js

@@ -226,7 +226,7 @@ class ResolutionRequest {
         realModuleName => {
           const searchQueue = [];
           for (let currDir = path.dirname(fromModule.path);
-               currDir !== '/';
+               currDir !== path.parse(fromModule.path).root;
                currDir = path.dirname(currDir)) {
             searchQueue.push(
               path.join(currDir, 'node_modules', realModuleName)