Curl HTTP wrapper now uses a condition variable in its run loop.
Lowered timeout in HTTP client unit test.
Feed items are now updated within a database transaction.
Fixed various issues with duplicate item detection.
Improved support for cancellation of feed updates during shutdown.
UI tweaks
Lowered default checksum retain count to 100.
Daemon now obtains an exclusive lock on the PID file.
Fixed bug in item checksum cleanup query.