Make LNPBP standard

[dr-orlovsky]

I propose to put the spec as one of LNPBP standard and make one of official protocols (alongside Storm for now, which is much more complex and underspecified). If you like the idea feel free to open PR to https://github.com/LNP-BP/LNPBPs using template https://github.com/LNP-BP/LNPBPs/blob/master/lnpbp-template.md

It is not required to fill in all the sections for now; just put the existing text into the "Specification" section, plus the existing intro from the README will make great Motivation section. As a standard number you can use LNPBP-39.

CC @grunch @zoedberg @fedsten @nicbus

[fedsten]

Sorry for the late reply, we agree with the idea of adding it as a LNPBP standard. We will work on the PR sometime in the near future.