allow queries for boolean values

  def matches?(event)

    @filters.all? do |filter|

      if !event[filter[0]]

      if event[filter[0]].nil?

        false

      elsif filter[1] == :equals && filter[2].is_a?(String)

        event[filter[0]] == filter[2]

        event[filter[0]].to_s == filter[2]

      elsif filter[1] == :list_include && filter[2].first.is_a?(String)

        filter[2].include?(event[filter[0]])

        filter[2].include?(event[filter[0]].to_s)

      elsif filter[1] == :exists

        !!event[filter[0]]

      elsif !(event[filter[0]].to_s.match(/^[0-9]+(.[0-9]+)?$/))