Update IntelliJ to version 14.

Version was previously 13.1.5, new version is 14:

* blog.jetbrains.com/idea/2014/11/intellij-idea-14-is-released/
* https://www.jetbrains.com/idea/download/
Merge pull request #7173 from nathankleyn/intellij-14

Update IntelliJ to version 14.