Version bump to 2021.1

Version bump to 2021.1rc1 (kytos#1244)

Merge pull request kytos#1224 from hdiogenes/version-bump-2020.2

Version bump to 2020.2

Version bump to 2020.2rc1 (kytos#1223)

Version bump to 2020.2b3 (kytos#1213)

Merge pull request kytos#1194 from hdiogenes/changelog-and-version-bump

Changelog and version bump for 2020.2b2

Merge pull request kytos#1160 from hdiogenes/version-bump-2020.2b1

Version bump to 2020.2b1

Update CHANGELOG.rst (kytos#1115)

Co-authored-by: Humberto Diógenes <[email protected]>

Merge pull request kytos#1076 from hdiogenes/master

Version bump to 2020.1rc1

Update CHANGELOG.rst