FuzzyEq should include a method that accepts an epsilon value

[brendanzab]

The std::cmp::FuzzyEq trait should have a function that accepts a user defined epsilon value. I'm thinking something like:

pub trait FuzzyEq {
    pure fn fuzzy_eq(other: &self) -> bool;
    pure fn fuzzy_eq_eps(other: &self, epsilon: &self) -> bool;
}

[catamorphism]

Fixed in 5e77d55