Added Windows support: split out platform-specific network connection code; worker pool cleanup in runTunnel is now asynchronous
Fixed: potential nil pointer access
Fixed "cannot start a transaction within a transaction" bug due to missing transaction cleanup; fixed transaction retry logic; enabled sqlite shared cached and WAL mode
Disabled sqlite shared cache mode: server entry cycle read transactions were blocking fetch remote server list write transations
Implemented connect timeouts
Merge pull request #6 from rod-hynes/master

Builds on Windows; implemented connect timeouts; bug fixes