Added support for downloading/syncing images from a specified album

[csimonsson]

This is my very first pull requests, sorry if I made some mistakes, but I needed to sync a local folder with a specific album so I created this new command for the CLI.

[csimonsson]

Any suggestions for improvements would be of great value!

[bo0tzz]

Good stuff! I'll leave the main review to @alextran1502, but there are a few things I would like to see:

• Can you have the album input be by UUID instead of name? That's a bit more robust, and means you don't need to loop over all the albums to find it. You should be able to get the UUID from the album view URL on the web client
• I would prefer if this command just downloads the full album, without deleting anything. I understand that your usecase is sync, but in a more general scope I think files being deleted is probably undesirable.

Thanks for the PR!

[csimonsson]

Thanks for the feedback! I'll change to AlbumId!

Regarding the deletions; this is disabled by default and the --delete option is used to enable this (same behavior as in upload command).

By doing so there's both a "download only" and "full sync" functionality.