Moved sysdb and sysdbd sources to src/tools/. Also, moved all purely private headers to that directory as well. Renamed some files for greater consistency.
daemon: Added "Listen" config option. The main thread listens on all configured addresses and serves requests through the frontend socket module. The backend collector loop now runs in its own background thread.
daemon: Treat parser errors different from daemon/libsysdb errors.
Renamed the project to SysDB (System DataBase). This name more closely resembles the actual intent / goal of the project. The prefix for defines / function / etc. has been changed to sdb_.
Added missing daemon/config.h.