Add git ignore for system files and exe
Added DS_Store to ignore
Add extension .exe to testUname
First attempt at correct output for uname

* Only tested on MAC (and thus failed)
Required Output:
    System name: Linux
    Host name: newCS
    OS Release: 3.13.0-36-generic
    OS Version: #63-Ubuntu SMP Wed Sep 3 21:30:07 UTC 2014
    CPU Type: x86_64