Improve the OpenRPC Playground code to provide better dev docs

[lyonsil]

https://github.com/open-rpc/playground

Here are some ideas after working on the initial implementation of dev docs:

• Text wraparound and alignment problems in the tables when things don't fit into a single line
• "Websocket" dropdown still visible despite "uiSchema[appBar][ui:transports]=false" in the URL which should hide it
• JSON-RPC message creation always defaults to "id" of 0, This should pick something random (number or string fine)
• Websocket connection indicator UI doesn't change when the connection is broken, making it look like you're still connected
• If a schema reference in the OpenRPC doc points to a 3rd party site, the whole UI breaks without any clear errors in the editor view
• The Playground repo is on Node 14 and has lots of errors/warnings about dependencies with security problems and deprecated versions
• There are some existing, open issues that would be nice to fix. For example, Support OpenRPC Spec 1.3.2 in Playground open-rpc/playground#606
• URL fields should be clickable URLs, not just plain text