QA:Testcase tuna cpu isolate

Description

this case test the functions of tuna, use it to isolate cpu

How to test

1. save the initial tuna setting

 tuna --save old.tuna

2. show tuna setting

 cat old.tuna

3. use tuna to isolate cpu 0

 tuna --cpu 0 --isolate

4. save the new tuna setting

 tuna --save new.tuna

5. compare two setting

 diff old.tuna new.tuna
 echo $?

Expected Results

1. return value in step 5 should be 1, it shows that tuna isolate successfully