zotero-cli, accept args like zotero://select/groups/2129771/items/A4N8WK7U

For example,
```
zotero-cli --group-id zotero://select/groups/2129771/items/A4N8WK7U
```
should be valid - zotero-cli should just extract the group and discard the rest.

Simiarly,
```
zotero-cli ...... --key zotero://select/groups/2129771/items/A4N8WK7U
```
should extract the item key and group.