Merge branch 'release/v2.2.0' into develop

* release/v2.2.0:
  Bump version to 2.2.0.
Documentation: Add heroku remote url in Readme.
Bugfix: Fix today computation on IE.
Bugfix: Use custom version of docpad for utf8 bug fix.
Bump version to 2.2.1
Merge branch 'release/v2.2.1'

* release/v2.2.1:
  Bump version to 2.2.1
  Bugfix: Use custom version of docpad for utf8 bug fix.
  Bugfix: Fix today computation on IE.
  Documentation: Add heroku remote url in Readme.