ConstantsComparator: The old code used `abs(x-y)/abs(x+y)<= epsilon` when comparing two numbers for equality (modulo relative precision). This is weird when x and y have different signs and potentially even causes a div by 0 whenever x=-y. Moreover the templating was awkward, causing a lot of code duplications and a Warning with clang.
Distribution[WithReward]: replaced forward declarations of ConstantsComparator by actual includes as the forward declarations caused some ambiguity regarding the template parameters.
Tim Quatmann