message: docs: fix version in changelog
diff: -# 3.6.1 / 2018-07-30
  +# 3.7.0 / 2018-07-30
  - ci: Fix publish step in circle config (https://github.com/segmentio/analytics.js-core/pull/97)
  - build: Replace robo with np for releasing (https://github.com/segmentio/analytics.js-core/pull/96)
  