Introduction of plugins directory

This directory used to store some third party jar package dependency by connector running, such as jdbc drivers.

!!!Attention: If you use Zeta Engine, please add jar to $SEATUNNEL_HOME/lib/ directory on each node.

directory structure

The jar dependency by connector need put in plugins/${connector name}/lib/ dir.

For example jdbc driver jars need put in ${seatunnel_install_home}/plugins/jdbc/lib/