default targetSdkVersion to same level as platformTarget
default targetSdkVersion to same level as platformTarget

pfn/android-sdk-plugin,aafa/android-sdk-plugin,aafa/android-sdk-plugin,dant3/android-sdk-plugin,aafa/android-sdk-plugin,pfn/android-sdk-plugin,dant3/android-sdk-plugin,pfn/android-sdk-plugin