backlog/207_212_fiware_service_path

This PR implements/fixes several backlog features and issues:

* Use the `fiware-servicePath` header (https://github.com/telefonicaid/fiware-connectors/issues/212)
* Common character set when naming persistence elements (https://github.com/telefonicaid/fiware-connectors/issues/207)
* The organization is not created in column mode anymore (https://github.com/telefonicaid/fiware-connectors/issues/181)
* Appropriate slash occurence treatment in fiware-servicePath (https://github.com/telefonicaid/fiware-connectors/issues/263)

After merging the PR https://github.com/telefonicaid/fiware-connectors/pull/261, this also includes:

* iot_support at tid dot es as official contact email in all the source file headers (https://github.com/telefonicaid/fiware-connectors/issues/260)

DO NOT MERGE YET
I understand that commit https://github.com/telefonicaid/fiware-connectors/commit/415654791c473ce5eec0d7cb1d03b27ed129b93c includes modifications in the code to implement what we talk recently (i.e. remove the initial "/" in servicePath and the special treatement of the ServicePath == "/" case). However, that commit doesn't include changes in the documentation.

Not sure if this is the rigth document to be modified, but I think modification should have been modified to talk about that. Or maybe I'm wrong?