Cleanup new website a bit

[KyleAMathews]

Comment out links to:

• Writing clients (we'll get this eventually but it's not critical right now)
• Connectors (they don't exist yet so let's not worry about documenting them atm)

Fill out "Shapes" page — there's good language on the old website we can copy.

[samwillis]

We need to significantly flesh out the details on the Typescript client page:

• the interface of ShapeStream listing all props/methods
• what are it's arguments
• whats the interface of messages
• how to unsubscribe
• how to get the offset to persist it
• how to restart a shape from an offset

then all the same for Shape

[KyleAMathews]

This issue is pretty vague — @samwillis want to create a new issue with your ideas to improve the typescript client page?