Don't automatically include native artifacts attached to this project in the list of dependencies.
Native artifacts built in the project will still be included in the APK.
Create Makefile with variables having absolute path instead of relative.
Remove MakefileHelperTest as this was all testing construction of relative paths.
Much simpler and clearer collection of native library folders when building APK.
Moved ndkOutputDirectory to AbstractAndroidMojo as it is shared by NdkBuildMojo, AarMojo, ApklibMojo and ApkMojo.
Renamed 'ndkArchitecture' variables to 'architecture' to disambiguate from a similarly named class attribute.