Starting to set up to find mutation classes up to permutation of vertices
Adds generics support to the mutation class size tasks. This should mean that the methods in MutClassSizeTask can be integrated with the abstract class and then the only thing that needs specifying to change behaviour is the generic type of matrix.
Genericifies the pools
Trying to move over to in matrices rather than doubles
Using int matrices all tests pass
Fixes bug with pool caching
Fixes problem in demos from matrix change