Read appToken and logLevel from AndroidManifest.xml
Implement event buffering
Always send session packages immediately
Add property environment to recognize testing activities
Add pseudo environments unknown and malformed
Add TODOs to markdown files
Add property defaultTracker for preinstalled apps
Attach referrer to each session package
Update README
Remove comment from README
Update migrate.md
Update copyright dates
Reformat README
Update version to 2.1.0