[Streamline Development Lifcycle] Fix backward incompatibility and improve 'dev mode' deployment policy

The original Streamline split the KIE-Server deployment in two categories based on KIE-Server mode:

• DEVELOPMENT: just SNAPSHOT
• REGULAR: just non-SNAPSHOT

This decision breaks, regardless of the default option, the BC+Kie-server existing behavior. And such breaking backward compatibility is not acceptable, the reason this issue became a blocker.

Adding to that, we also noticed that BC has an important inconsitency: new projects are not SNAPSHOT by default, and samples are SNAPSHOT by default.

So, after discussing with stakeholders, here's the agreed consistent solution:

• KIE-Server will be kept default to DEVELOPMENT mode, but the REGULAR mode will be renamed to "PRODUCTION" mode. The `REGULAR` word might be misleading, while the "PRODUCTION" word is more clear of the purpose and calls for a conscious decision with the config flag.
• KIE-Server and BC will allow deploying on DEVELOPMENT anything (SNAPSHOTs or not)
• BC will default new projects to use SNAPSHOT, making it consistent with our samples AND general development best practice.