Get share information

[sushibear]

Is your feature request related to a problem? Please describe. We would like to find out if a share for a file or folder already has been created, before we create another one. As far as I can tell, this is not possible.

Describe the solution you'd like Instead of using createShare to get the share.url, I think it would be better to have a command like getShareInfo or such and call this API as described here: https://docs.nextcloud.com/server/latest/developer_manual/client_apis/OCS/ocs-share-api.html#get-shares-from-a-specific-file-or-folder

Regards and thanks alot for this great package!!