Use Paste Chat Log to replace custom MessageLog CSS/Components

[ayyrickay]

https://paste.twilio.design/components/chat-log

This should be a fairly straightforward replacement because the Dev Phone message log is organized in very similar components. It's worth doing a bit of preliminary digging to check for feature parity, however. Do we have any information that would be lost by switching to the Paste chat log? Any functionality that would be lost?

My hunch is that it's all positives, though - namely for fixing the need to scroll when messages overflow in the log.

[ayyrickay]

This could potentially solve #167 (needs more investigation but it doesn't seem like they're considering the input component for outbound messages)

Would certainly make #134 and #135 simpler, because the chat bubbles already handle media