Warning for automatic conversion of addresses from cashAddr to slpAddr

[jcramer]

The explorer allows users to enter in a cashAddr to display BCH and token balances. This page view provides these visitors with an automatic conversion of the cashAddress to slp format which can lead to pretty bad user experience problems. Namely, if the user doesn't have an SLP wallet he may think that he can just use that slp formatted address to accept SLP tokens. Little does the naive user know, his non-SLP wallet will burn his tokens.

Would a PR be welcome to fix this problem using a button/modal dialog warning message before displaying the address conversion?