WIP update to 3.0.2 for draft 6 and draft 7 support

I tried to prepare an update to 3.0.2, I merged the upstream tag, updated changelog and packages description with add of draft 6 and 7. I tried to redid the fixed version patch. I temp. commented the other patch that I not understand how to update it with a fast look. Looking requirement in setup.cfg I found these added: attrs>=17.4.0 pyrsistent>=0.14.0 six>=1.11.0 python-attrs and six seems present in repo with needed version but pyrsistent seems in blocked in new queue: https://ftp-master.debian.org/new/pyrsistent_0.14.10-1.html

python-json-pointer >=1.13 in the extra I didn't know if really need because 1.13 is missed actually in debian repo :(

Any help is appreciated, or if someone expert want complete this also better Sorry for my bad english.