0.4.1

Changelog

de6b14b Support stack driver severity levels.
e91479b accept stackdriver 'severity' tag as level
34aa9a8 support more time format
56a03cf Merge branch 'master' of github.com:aybabtme/humanlog
e40d8fc fix release URL
ccfa4da Fix indentation
119d3b3 Add YYYY-MM-DD hh:mm:ss date format to parser