Added import configuration module stub and unit tests
Implemented AvroFileTarget in importtools module.
Added tests for AvroFileTarget.
Implemented DataSource and TextFileReader
Test chromosome field with and without processing
Implemented HDFS target
Added exceptions and factory methods
Added exception and factory method
Cleanup
Implemented variant import utility
Added code
Updated test
Improved logging
Added logging configuration module
Merge pull request #6 from ITMI/import_config

Import config