Implement LiveCode Engine for Cloudflare

[anandology]

Implement the simplified API specified in #12 to run on Cloudflare Workers.

Cloudflare workers support running Python. It is serverless and already sandboxed. Timeouts are already take care.

Experiment with running python code in cloudflare workers and see if livecode can be implemented as a cloudflare worker.

Tasks:

• Create a new file engines/cloudflare.py with the required code
• Document how to install it on aws and use it