Removes bugsense from the demo project

It was using an old version of the sdk and also this fixes the build because we were using the wrong name (now it is Splunk)
Fixes the build by adding the missing application tag
Updates build tools to latest and uses the right plugin id
Removes unnecessary Manifest file
Creates debug config instead of release and removes unnecessary stuff
Removes redundant stuff allready defined in gradle and fixes lint issues
Merge pull request #174 from novoda/fix_the_build_and_tidy_up

Fix the build and tidy up