Create Python connector

[pkiraly]

The Py4j project enables Python scripts to call a Java API. Implementing this enables Python developers to use QA Catalogue's API from their Python script in processing bibliographic records, so they will be able to utilize the rich feature set for MARC21, and also for Unimarc and PICA such as reading different serialization formats, preventing memory problems (PyMARC reads the show XML file into memory), access and use information stored in Avram schema and many more.

To enable to connection once should start a dedicated Gateway (from command line), and Python communicate it via a HTTP port. Once the Gateway is available the script can access its methods and properties.