Changed book title sorting from lexical to numerical, Fixes #21

[jrhedman]

I looked at Kotlin's natural-order but it uses lexical ordering which would do the same thing.

I built a function that will handle doing a comparator using numeric sorting which is what the issue is addressing.

Link on lexical vs. numeric sorting for posterity.

[mattttvaughn]

closing this as stale, feel free to reopen if you continue work on this