Updated the operator, fixing a bug with the database connection, where if a network is deleted and still has pods, it would break it

Updated l2sm database schema and operator to go along with it. Now there are more constraints in the database and errors are handled accordingly, so the application is more robust against errors

Removed criptography dependency in the l2sm operator, as it has security risks attached to it and it's no longer needed

Following the python guidelines of usage, the operator's Dockerfile has been updated, to use a requirements.txt outside the dockerfile.

Identation fixes

Modified the switch subsystem to use a new initiation script that runs as a full process within the container. The script is now invoked using CMD in the Dockerfile, eliminating the direct creation of VXLANs. This change enhances the containerization approach and ensures a more streamlined and efficient initiation process.

This adjustment aligns with best practices for running processes within containers and improves the overall architecture of the switch subsystem.

The source code directory has been moved from ./build to ./src.

This change was made to improve project organization and follow best practices.