Adds a new DataLogger class, that is now resposible for logging search, search-result and transfer Bundles. The DataLogger is disabled by default and can be enabled using the property de.netzwerk.universitaetsmedizin.codex.gecco.dataLoggingEnabled or environment variable DE_NETZWERK_UNIVERSITAETSMEDIZIN_CODEX_GECCO_DATALOGGINGENABLED.
de.netzwerk.universitaetsmedizin.codex.gecco.dataLoggingEnabled
or environment variableDE_NETZWERK_UNIVERSITAETSMEDIZIN_CODEX_GECCO_DATALOGGINGENABLED
.fixes #81