Improve examples

[dougollerenshaw]

Changes:

• Moved all examples to a single yaml file instead of standalone txt files
• Added more examples and improved existing examples
• Added functionality to select from all possible examples when clicking "Use Example"
• Made some more changes to response parsing logic in api_utils to avoid errors
• Added to system prompt to help avoid json errors and to avoid issues with newlines in code
• Added pyyaml to requirements