unset db during build
unset db during build

build step must not require a database connection (to support db-less build server)
This change helps finding problematic code during development when a db exists

koala-framework/koala-framework,kaufmo/koala-framework,yacon/koala-framework,nsams/koala-framework,nsams/koala-framework,yacon/koala-framework,kaufmo/koala-framework,nsams/koala-framework,kaufmo/koala-framework,koala-framework/koala-framework,yacon/koala-framework