the readme doesn't mention /v3

[karelbilek]

Very randomly I have noticed I am using old version of this package, because readme is still showing old import path of v1.

I don't want to make a PR myself because I am not sure if v3 is safe to use :)

[jszwedko]

Hey! Thanks for pointing this out. v3 is the latest release and is safe to use. A PR to update the docs would be welcome :)