.dat serializations get _really_ big for rule lists that don't have a trailing "\n"

[pes10k]

> let ab = require("ad-block");
undefined
> let input = fs.readFileSync("input.txt", "utf8").trim()
undefined
> client = new ab.AdBlockClient()
AdBlockClient {}
> client.parse(input)
undefined
> client.serialize().length
96697404
> client2 = new ab.AdBlockClient()
AdBlockClient {}
> client2.parse(input + "\n")
undefined
> client2.serialize().length
518462

[pes10k]

input.txt

For use in the above example