Make more flexible function for user supplied url

[vanithaak]

1175

As of now the function is able to detect a key like texas-barnraising from a longer URL like https://archive.org/details/texas-barnraising

• people may input either a full URL like https://archive.org/details/texas-barnraising, or they might put just the key like texas-barnraising -- they might even put just archive.org/details/texas-barnraising. A function which would output texas-barnraising in any of these three cases

Now we want to fetch images even when the user supplies a url with http:// in the beginning

[vanithaak]

@segun-codes will work on this issue, as suggested by @jywarren. Thanks!