1. Provide a Storable instance for AI.MEP.Types.Gene
   and make the Chromosome a Data.Vector.Storable.

2. Improve code generation. Features:
   a) Removal of dead (unused) expressions
   b) Subexpression elimination, e.g. x0 / x0 -> 1

3. Improve the demo: provide a CLI interface to work
   with external data

4. Performance tuning and benchmarking using Criterion package.
   Hint: use of matrices featuring O(1) memory access
   instead of lists of vectors ([Chromosome a], [Phenotype a]),
   might improve the speed of such operators as binaryTournament.