Eckity

Several improvements:

- Termination Checker can now also be a list. In that case, early termination is performed if any of the termination conditions apply.
- Generations now range from 1 to max_generation, instead of 0 to max_generation - 1.
Individual now contains informative fields - id, gen, cloned_from, selected_by and applied_operators.
- Vector and its subtypes can now receive a list of the genome (vector cells) as constructor argument.

**ProcessPoolExecutor**
Previously, fitness evaluation tasks could only be submitted to a `ThreadPoolExecutor`.
From now on, the tasks can also be submitted to a `ProcessPoolExecutor` (enhanced performance in some cases).

When initializing an instance of `SimpleEvolution`, use the parameter `executor=process` for a `ProcessPoolExecutor`, or `executor=thread` for a `ThreadPoolExecutor` (the default is value is `thread`).

Multi-Objective Evolution
MOE - multi-objective evolution - from now on you could use EC-KitY to run an evolutionary algorithm with multiple objectives, to receive the Pareto front and find the best solution(s) for you.

IndividualEvaluator.evaluate signature change
`IndividualEvaluator.evaluate` now also receives the entire sub-population individuals, and not only the current individual.
Useful for non-simple cases in which the individual's fitness also depends on the rest of the individuals in its sub-population.

bug fixes for float vector and tests

Bugfixes to GA `IntVector`, `FloatVector` and their appropriate `Creator` classes