Delete package-export.apk before rebuilding to avoid aapt warnings
about using -f on existing packages.
Change-Id: I189486c4b3bd5fa46eff2e3b6a244d28329e7f02
Add support for running aapt to generate R.java and Manifest.java,
compiling java into jar, adding resources to the jar to convert it
into an apk, signing the apk, and zipaligning the apk.
Change-Id: I7a73fef590d07f35b3d0b56a8571780c09bb10ae