Container skip database setup during plugin enable if so configured

The container entrypoint script should skip running the database command when COMANAGE_REGISTRY_SKIP_SETUP is set even if COMANAGE_REGISTRY_ENABLE_PLUGIN is being used. The effect should be that the symlinks are set up but the schema check is not run. This is useful when the deployer knows the plugins have been previously enabled and the schema check is not necessary and instead wants a faster startup.