Renamed ProvinciaWIFI synchronizer to ProvinciaWifi for consistency
#178
Renamed ProvinciaWIFICitySDK synchronizer to ProvinciaWifiCitySdkTourism for consistency
#178
Added synchronize action in admin #178
Use django.utils.module_loading.import_by_path to import synchronizers #178
Renamed synchronizers in order to simplify their python paths #178
* renamed synchronizer files
* added list of synchronizers in __init__
* updated DEFAULT_SYNCHRONIZERS setting
* updated docs #126
Simplified NodeExternal model in nodeshot.interoperability #178