Unlink port file on bad start

On a bad start, e.g. an invalid initial cycle time, the port file can
get left behind. This change fixes the problem.
Merge pull request #890 from matthewrmshin/fix-port-file-unlink-in-bad-start

Unlink port file on bad start
Add error handling for database failure.
Merge pull request #892 from arjclark/suite_shutdown_on_loacked_db

Add error handling for database failure.
Updated change log for 5.4.8.