Convert ENS address to link functionality

EAL will now find .eth ENS domains on the webpage and automagically link them to your chosen block explorer. Here's what it looks like with the highlighter enabled.

If the block explorer doesn't support ENS domain lookup, then it'll be visible to you in the webpage with a nice red underline, and it won't take you to the block explorer site.

Really big thanks to https://github.com/Samyoul for doing this!