Update README, release version 3.5.10

Bump version to v3.5.6, add backup dns for bapi

Remove delete urgia id form demo.py

Bump version to 3.5.4, add requests-toolbelt to requires

Bump version to 3.5.2

Add update message

Add new args offset for illust_related()

Update README.md

Bump version to 3.3.5

Revert test comments