Removed all the invalid references to XAppView
[Doing-239] Removed native app implementations from xFaceLib. Instead, design it as a standalone plugin.

1. Removed native app implementations from xFaceLib.
2. Removed StoreKit.framework from template project.
Added isDefaultAppWebView method to XUtils, it would be invoked by XAmsExt (and the like) during its creation process.
Added build action 'clean' to cordova/build in order to fix xmen build error

error info:
fatal error: file 'xFace/XLog.h' has been modified since the
precompiled header 'HelloxFace-Prefix.pch.pch' was built
Removed method XUtils:: resolveSplashScreenImageResourceWithOrientation which is no longer being used.