Add some bugfixes

...son/.master/HandsOnPerformanceOptimization-solution.ipynb

...Handson/.master/HandsOnPerformanceOptimization-task.ipynb

...OWER/Handson/.master/HandsOnPerformanceOptimization.ipynb

...imizing_POWER/Handson/HandsOnPerformanceOptimization.html

...mizing_POWER/Handson/HandsOnPerformanceOptimization.ipynb

...timizing_POWER/Handson/HandsOnPerformanceOptimization.pdf

...son/Solution-Notebook/HandsOnPerformanceOptimization.html

...on/Solution-Notebook/HandsOnPerformanceOptimization.ipynb

...dson/Solution-Notebook/HandsOnPerformanceOptimization.pdf

3-Optimizing_POWER/Handson/Task2/Makefile

3-Optimizing_POWER/Handson/Task2/Solution/Makefile