Extract model dependent functions to a new module
Rename `model` occurences to `algorithm`

Change all occurrences of `model` because new behaviour should be called by this name
Introduce config record for various constant parameters in parallant
Introduced algorithm behaviour (parallant_seq, parallant_tiled)
Merge pull request #4 from ParaPhraseAGH/model_behaviour

Introduce config, extract model, add algorithm behaviour