Address autocomplete improvements

[nventuro]

• Click on image to open dropdown
• Image should be a plus sign when address field is empty, to prompt clicking on it, only change to ERC20 when valid token (but image-less) is entered
• Scrolling is broken
• Not all items are displayed
• Not sorted on all platforms
• Add a placeholder saying “Click here or paste an ERC20 token address” (form label)