Add Range#overlaps to deal with constructing an OVERLAPS clause for queries in Sequel

overlaps.rb

class Range
    def overlaps(range)
        Sequel::SQL::PlaceholderLiteralString.new(
            "(?, ?) OVERLAPS (?, ?)",
            [
                self.first, self.end,
                range.first, range.end
            ],
            true
        )
    end
end

module Sequel
    module SQL
        class QualifiedIdentifier
            def <=>(other)
                return 0
            end
        end
    end
end