Add ability to copy json

[tnrich]

Hey there,

First off thanks for the awesome tool! It definitely is a joy to work with alongside redux :)

One minor issue I've been noticing is that it is currently quite tedious/impossible to copy large blobs of json stored in the redux state using this tool. It would be awesome if there were an easy way to do this.

Please consider adding a little "copy" button next to the "pin" button, or perhaps just allowing users to view the state as pure json.

It would be greatly appreciated!

Thanks!

[alexkuz]

I would go with "Raw" checkbox in the right bottom corner probably.