Make blockie identicon circular with more breathing room

src/popup/views/addressDetail.js

@@ -49,6 +49,7 @@ function show() {
     img.width = 48;
     img.height = 48;
     img.style.imageRendering = "pixelated";
+    img.style.borderRadius = "50%";
     blockieEl.appendChild(img);
     $("address-dot").innerHTML = addressDotHtml(addr.address);
     $("address-full").dataset.full = addr.address;