Added additional icons

New icons:

* Google Chrome Canary:
![google chrome canary](https://cloud.githubusercontent.com/assets/5241697/3605610/3725e2aa-0d2d-11e4-92f3-eac66c23ecea.png)

* Xcode 6 Beta:
![xcode 6 beta](https://cloud.githubusercontent.com/assets/5241697/3605608/30f736d6-0d2d-11e4-90b3-0be4ee8d62c5.png)

* Bitcoin-Qt:
![bitcoin](https://cloud.githubusercontent.com/assets/5241697/3606044/c44de4a8-0d31-11e4-9132-3e28fd47d11d.png)

* Parallels:
![parallels](https://cloud.githubusercontent.com/assets/5241697/3606735/ccf3dd02-0d3a-11e4-98ab-e8c0fa3c1a67.png)