Given an org ID, find the publisher

E.g.:

```python
import iatikit

org_id = 'GB-COH-07676886'

org = iatikit.data().publishers.find(org_id=org_id)

print('IATI publisher "{org_name}" has org ID: {org_id}'.format(
    org_name=org.name,
    org_id=org_id))

# IATI publisher "Publish What You Fund" has org ID: GB-COH-07676886
```