Add tabbed service views + portfolio, category service information

Enhance Our Services site area to be called Services instead with an index page displaying a tabbed view of all services and services listed by team.

This is to offer easier navigation to particular service pages, and easily & quickly look up a service as part of service management or other referencing.

This is hoped to replace more of what's in:

• DevOps Division Structure
• DevOps Team Services

To better support this, also add into services.yml these new keys:

• portfolios: List of the portfolios
• service_categories: List of service categories

Then further update services.yml:

• Specify which portfolio each team is
• Specify which category each service is