Improve ease of use

[Crzyrndm]

The first cut is workable, but far from user friendly. Naming is a major issue, but I'm probably not particularly idiomatic in many places, and the lifetimes involved also make things slightly more awkward than I would like

A fully worked example for a standard RTU master and slave device (coils, inputs, input regs, holding regs, device ID) would help highlighting points of friction and showing improvement over time. Will also be helpful for benchmarking memory usage