New blueprint for React & Python single page app

[rosmo]

New blueprint for React & Python single page apps, both with global and regional load balancer. Includes automation for extracting Content-Security-Policy headers.

I applicable, I acknowledge that I have:

• Read the contributing guide
• Ran terraform fmt on all modified files
• Regenerated the relevant README.md files using tools/tfdoc.py
• Made sure all relevant tests pass

[ludoo]

Hey Taneli, I don't think this is a good example to have here: not only because we're trying to move awayrationalize blueprints, but more importantly because we focus on Terraform. Anything else should at best have a supporting role, or not even be there.

@juliocc WDYT?

[rosmo]

I have no particular opinion whether it is a good example or not, but 1) I've had multiple customers ask about this, 2) There is no documented pattern out there right now. Make of it what you will.