project: rename db to project path

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
project: add db/refs directories permanantly

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
core: unify event handling

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>
project: load and unload callback functionality

Signed-off-by: Hagen Paul Pfeifer <hagen@jauu.net>