bump version to 2.0.1

update CHANGELOG with 2.0.0 release

bump version to 1.0.2

0.18.3: warn about Python 2 usage

bump version to 1.0.1

Bump changelog timestamp

Bump to 0.18.1 to fix pypi obstreperousness

Also include contriburors update.

Merge pull request mitmproxy#1602 from cortesi/scriptdocs

docs: stub out new script documentation

bump version