Document `Cannot access "buffer.Buffer" in client code` workaround

[ThaisRobba]

While following up on the installation and usage guide, I bumped into this issue - basically, buffer is not available on client side and we need to manually install it. A simple yarn add buffer or npm i buffer and restarting the dev server should fix it for most (stack overflow thread).

Perhaps buffer should be added as a dependency of blinkdb?

[maradotwebp]

Sounds good. I'll test if this causes any issues with using blinkDB with node.