Additional features for CSW QGIS plugin

 - Added ability to get bbox extension from any loaded layer in qgis.
 - Added ability to get bbox using geolocation services.
 - UI tweaks to accommodate the new features. (UI was updated with Designer)
The geolocator always returns one result; the most relevant one. After the user hits return, the where lineedit widget updates itself with the name and populates the bounding box. If the user is happy with the provided location then he can go ahead with the search function. If not he can always refine the location string with more information, e.g. by adding a country. 

It is possible for the geolocator to return n locations, so a user might choose from it. I think i can implement if it helps 

It is possible to pass an extra argument to bias the geolocator on where to focus if one wants - the bias also takes care the languange of the returned location. 

eg if you set the domain for google geolocator to "maps.google.gr" the returned string would be in greek. Its easy to implement such functionality, but i haven't thought a workable approach to that yet.