Allow for editing of logins/credentials through the CLI #269

My list of logins was build through many providers over the years (3 browsers, other vaults, etc.) and now contains many duplicates. The web interface, no matter how great, will never suffice as a tool for mass editing. If the CLI had actions to read & update login data (email, url, etc.) one could easily put a script together that would find duplicates and merge them.