Remove duplicate sentence from the README file.
Clean up Makefiles.
Fix "make dist".

Fixes #4489
Fix the ASSERT() macro.
Fix deadlock in Service::RemoveDowntime().
Fix: ::Start must be called after restoring the state file.

Fixes #4654
Fix state file functionality.
Implement cluster event for SetForceNextNotification.
Implement cluster events for notifications/flapping.
Build fix.
Config Conversion: Fixes.

refs #2743
Implement cluster events for acknowledgements.
Merge remote-tracking branch 'origin/master'
cluster: Fix duplicate acknowledgement comments.
Check if flapping is enabled.
Config Conversion: always add type NotificationFilterProblem.
Configuration: Remove 'local' identifier.
Config Conversion: Detect user macros properly.
Config Conversion: Skip user macros for non-command objects.
Increase minimum number of threads.