* A solution with Actor Model concurrency and MappedByteBuffer
* fix test cases
* revert back the file name to original
* cache String hashCode calculation via composing with Key object
* fix wrong key caching and eleminate duplicate String creation between actors
* update possible char count in a line, fix calculate_average.sh
* increase possible line length to 256 bytes, much safer to cover 100 chars I hope
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Co-authored-by: Yavuz Tas <yavuz.tas@ing.com>
