Add retries and logging to GeoNames requests

This addresses #7705. GeoNames name searches failed with URLError when
a bad connection or url interfered with openurl. This allows retries
in the case of short-term issues and handles total failure by logging
and passing to the next geocoder.
Fix GeoNames URI
Merge pull request #31 from dpla/7705-geonames-error-handling

Add retries and logging to GeoNames requests