Applications template

[tomaspvk]

Addition of template application with module.

[cermmik]

• Please update also the README.md in Stream4Flow/applications/ directory.

• application_template.py -- add comment/description to module loading on line 29 -- provide common python documentation for functions (like kafkaIO module) -- new line to the end of the file

• kafkaIO.py -- add "# -- coding: utf-8 --" to the beginning of the file -- missing return value description in initialize_kafka_producer function documentation -- check if data were successfully sent to the Kafka (http://kafka-python.readthedocs.io/en/master/apidoc/KafkaProducer.html#kafka.KafkaProducer.send)