Added a configuration parameter that allows summary emails to be turned off
Merge pull request #103 from radonsky/Optional_summary_email_notifications

Added a configuration parameter that allows summary emails to be turned off
All uses of raw Enum types replaced by marker interfaces
Added comments
Changed JanitorCrawler’s resourceTypes() method to restrict the resulting EnumSet to contain ResourceTypes only
improved error reporting from the valueToEnum method
fixed unit tests
checkstyle cleanup
Merge pull request #104 from radonsky/fix_enumerated_types

Fix enumerated types
Merged latest changes from ‘Netflix/gradle-template’ single-project branch
BasicScheduler unit tests improved
fixed a PMD warning
Merge pull request #105 from radonsky/merge_latest_gradle_template

Merged latest changes from ‘Netflix/gradle-template’ single-project branch
Merge pull request #106 from radonsky/improve_basicscheduler_unit_test

BasicScheduler unit tests improved
fix image cleanup
Merge pull request #107 from Yelp/yejun_fix_image_cleanup

fix image cleanup