Resolve "best_track fails for tracks slices"

Closes #63

See merge request !43

Resolve "New KM3NeT Dataformat Release v1.2.4"

Closes #60

See merge request !42

Resolve "New KM3NeT Dataformat Release v1.2.3"

Closes #55

See merge request !36

Resolve "Parsing of HRV and FIFO status words"

Closes #59

See merge request !40

Resolve "Use km3net_testdata"

Closes #57

See merge request !38