v0.2.7 Release Notes: Fixed Gemspec

Albacore v0.2.7 is available via RubyGems.org

The only work done in this release was to fix the gemspec so that rubyzip is listed
as a dependency. To do this, Jeweler, the gem used to create the albacore gem, was updated
to v1.6.4 and the albacore gem was repackaged and pushed to rubygems.org.