fixing #508 

 * Querying Geoserver for the exact value
 * No need to escape `%` now which was appended on both sides of the query

If anyone here objects to removing the wildcard and can explain me why - I'm happy to return it. However usually if I query for `uga`, I plan on getting `uga`, and not `buga`, `duga` or `kuga` (represented by `%uga%`)