dedicating kind type and adding its methods.

[kehiy]

I've made a new type Kind which is equal to uint16. it supports fixed numbers of all Kinds. but the int type is basically int32 and int64 based on the target device (as far as I know), which can hold bigger numbers and it's unnecessary. Also, some methods were added for getting the range of a kind which can help in the relay or maybe client Implementations.

Example: https://github.com/dezh-tech/immortal/blob/main/types/kind.go

[fiatjaf]

I don't like the extra cognitive load for very little gain, but maybe, let me think about it.

[kehiy]

@fiatjaf That's OK. We can remove the type itself, but keep the methods!

[kehiy]

do you think we should close this one? i'm trying to make another pr but I made this one on the master branch. so, it seems i'm limited now.

[kehiy]

I close this and open it on another branch.