Styling for the request/response block

[sedovalx]

Now it is a JSON in the <pre> tag. But it should be possible to create a markup for Request:

• method
• uri
• query parameters
• headers (optional)
• body (optional)

Response:

• status
• protocol version
• headers (optional)
• content type (from headers)
• body (optional)

Error:

• message
• error type
• error message

[sedovalx]

Should support three types of the body content:

• text/plain
• application/json
• text/html

The type could be detected via Content-Type header.

[sedovalx]

Just one simple style for all for now. Possibly it won't be hard to attach something like google/code-prettify or hightlight.js