Updated the BCL readme file.
Updated the BCL readme file.

genexliu/NativeScript,hdeshev/NativeScript,NativeScript/NativeScript,NativeScript/NativeScript,genexliu/NativeScript,NativeScript/NativeScript,hdeshev/NativeScript,hdeshev/NativeScript,NativeScript/NativeScript,NativeScript/NativeScript,genexliu/NativeScript