Without this babel plugin when you try to debug in Dev Tools > Elements,
it displays the components with the styled-component name shown as a hash i.e.
`<div class="sc-EHOje dGUdfn">`, whereas previously with CSS/Sass it showed the class name.

This babel plugin displays the style-component name that we specified instead of a
meaningless hash i.e. `<div class="App__DivContent-sc-1l7hwf9-0 jhbGUD">`, where `DivContent`
is the name of the styled-component that we created.

- Add option to import a Parity Signer account. It is then stored in
local storage.

- Send transactions with Parity Signer accounts

- Refactor sendStore so that "token" (and chainId) is inside this.tx;
avoids having to pass `token` around every function, and it makes sense
to put it in the object since it is part of the tx info.

- Add account type (either node or signer) to accountsInfo

- Add account type to withAccount; output props are now `{account:
{address, type}}` instead of `{accountAddress}`

todo:
* add option to export json keyfile to backup
* clean up duplicated code in store