Write IO examples with and without associated programs to disk

[THinnerichs]

There should be two ways of doing this, both implemented:

1. written in human-readable way possibly as an inverse of Data.readfile(). Not necessarily applicable to all types and problems.
2. written for maximum flexibility and speed by serialization over Julia's Serialization module.

Both functionalities are crucial for DataGeneration.jl and ML4Herb.jl.