[#24] Capture error when we get a wrong API response
[#24] Update API query to make it compatible with older Solr versions

The following expression is not valid in Solr 1.X:

"q":"harvest_object_id:*"

It returns the following error:

'*' or '?' not allowed as first character in WildcardQuery

It has been replaced with:

"q":"harvest_object_id:[\"\" TO *]"