Split compilation for an architecture into its own method.
Split out the responsibilities of the cleanUp method and renamed to attachNativeLib.
Fixed up parameter defaults.
Simplified still further.
Resigned myself to the fact that NDK Executable just wants to build at the root folder.
Simplifying attachNativeLib
Removed unused properties of Ndk pojo.
Merge remote-tracking branch 'origin/master' into issue-360
Check missing build-tools
Merge pull request #381 from ldematte/master

Check missing build-tools
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.
Merge pull request #384 from william-ferguson-au/issue-360

Fixes for Issue 360