Metadata persistence in HDFS and MySQL

Partially implements the issue https://github.com/telefonicaid/fiware-connectors/issues/41

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This is an interesting discussion :) This is about Hive tables, not MySQL ones, which could not be automatically created due to a typing issue; there was no way to know if, for instance, a "degree" attribute type was an interger, a float or whatever other MySQL basic type. But using Hive I think there is no problem with the types because everything will be a string :) Thus, I think the Hive tables can be provisioned in order to support the remote querying of the data, independently they are in the "row" or "column" mode.