Setup circleci to test RPM install on docker centos instance

Pretty happy with it. 

The exports I did in testRpm.sh aren't great. But we can fix that later :smile: 
![image](https://cloud.githubusercontent.com/assets/6640874/4110670/96a674b4-31f5-11e4-9b01-0eba225282ed.png)

The two exports should be replaced with `source /etc/profile.d/kdb-plus.sh` to test the installed profile