Add logging for EventBuffering and DefaultTracker
Add documentation for pre-installed apps
Add comments about parameters eventToken and parameters
Return null if we can't access the ApplicationBundle
Log about malformed logLevels
Move LOGTAG to constants
Split checks for events and revenue events

Move checks to PackageBuilder
Fix logger, remove androidLogLevel
Merge pull request #25 from adeven/ImmobilienScout24-development

Cleanup
Make Logger methods public
Catch NullPointerExceptions for ActivityHandler.context
Update version to 2.1.2
Merge branch 'master' of git://github.com/adeven/adjust_android_sdk