list_ext 0.0.1

Dart extension method for Iterable and List.

[0.0.1] - 2020-03-26

• Method countWhere() - returns count of elements that satisfy the predicate [test].
• Method sumOf() - returns sum of int values by elements.
• Method sumOfDouble() - Returns sum of double values by elements.
• Methods sum() for iterables of int and double.