AC-FOVE: Split on A/t

* AggregationParfactor: split method for substitution of the form A/t
* ParameterizedFactor: changed precision value
* ParameterizedRandomVariable: rename method
* PredicateSymbol: corrected equals method
* Pool: correction on structures to test split on aggregation
parfactors.

Second part (and hardest) of splitting aggregation parfactors is
implemented and tested briefly. The code needs some improvement to
make it less verbose.
AC-FOVE: Split on X/A

* AggregationParfactor: split method for substitution of the form X/A
* Constraint: correct equals method to be symmetrical
* SimpleParfactorTest: removed test of renameLogicalVariable method
* Pool: correction on structures to test split on aggregation
parfactors.

Third part of splitting aggregation parfactors is
implemented and tested briefly. The code needs some improvement to
make it less verbose.
Constraint equals() method is now symmetrical, that is, A != B and
B != A are now considered the same constraint.
AC-FOVE: Multiplication with Aggregation Parfactor

* AggregationParfactor: multiplication and auxiliary methods
* SimpleParfactor: changes in multiplication methods to deal with
Aggregation Parfactors
* AggregationParfactorTest and Pool: set of tests for multiplication
involving Aggregation Parfactors.

There is a 'flaw' in the model because SimpleParfactor must be aware
of the existence of AggregationParfactors, even though they are both
Parfactors (interface).
Messing up with git configuration