bug/200

Fixes the issue https://github.com/telefonicaid/fiware-connectors/issues/200
The encoding function remains the same for both the service and the entity id and type. This must change in future versions, having a `encodeService` function allowing only for lower case alphanumeric and `_`, and a `encondeEntity` function allowing only for lower case alphanumeric, `_`, `-` and `.`.

Just informative.