Merge gradle template as of May 2013

Eureka's fallen behind in the gradle-template, this get it up to date. This adds a more stable release process, support for automatically publishing javadocs into gh-pages, upgrades to Gradle 1.5, and less strict header checking. Please merge at your convenience.

There's one problem with the current publishing which is putting signatures into the ivy files, but it's not uploading them. I also don't see any tags for 1.1.98. How is it being released? It's causing problems for other consumers of this library as of today.