Enabled building via make files for AOSP

Deleted the /gen folder and added it to the .gitignore file, as this can cause problems. This is mainly a file for eclipse to use when it builds and compiles the app. It's best this is regenerated by anyone who clones the project. It also conflicts with AOSP builds using make files.

I added the Android.mk make file for this app so that it can be built as part of an AOSP ROM, like mine.