CB-7044, CB-7299 Fix up PATH problems when possible.

Uses heuristics:
- Adds javac to PATH based on default install paths on Windows
- Adds javac to PATH based on JAVA_HOME
- Adds android and adb to PATH based on ANDROID_HOME
- Sets ANDROID_HOME based on location of "android"

bin/lib/create.js

@@ -196,7 +196,7 @@ exports.createProject = function(project_path, package_name, project_name, proje
     })
     // Check that requirements are met and proper targets are installed
     .then(function() {
-        check_reqs.run();
+        return check_reqs.run();
     }).then(function() {
         // Log the given values for the project
         console.log('Creating Cordova project for the Android platform:');