fix(configuration): fix error removing customization logos in a short…

… period of time

- Add plugin setting category: API_CONNECTION (related to hosts
  setting)
- Replace the category of hosts plugin setting
- Refactor the setting.store.file interface:
  - Remove configurable
  - Add configurableManaged and defaultBlock
  - Adapt the plugin settings defitions with these changes
- Remove the configuration block related to the API connections from the
  ConfigurationStore service to the plugin setting definition through
  the defaultBlock
- Enhance logging on ManageHosts