Implement distance calculation (repository layer)

[aldy505]

Create a new package under the repository package. Implement this. If possible, please include unit tests.
Tip: use haversine.

mock-shipping-provider/repository/distance_calculation.go

Lines 5 to 8 in 413bb3e

	type DistanceCalculation interface {
	// Calculate distance between two coordinate. It returns distance in kilometers.
	Calculate(from primitive.Coordinate, to primitive.Coordinate) (distance float64, serviceable bool)
	}

[khairulharu]

i work with this issue
i have already create pr