Add BuildConfig to ant SDK project.
The BuildConfig class contains a single boolean constant
called DEBUG which is true only for debug/instrumented builds.
This allows developers to create debug only code that's automatically
stripped from release builds.
Also fixed some issues with dependency check for other tasks, notably
the aapt task that would always find new files due to not filtering
out files that are ignored by aapt itself (hidden files, version control
11 files changed