##Step1. Load data set from raw txt files (features, test, train etc.)
##Step2. Merge train and test data
##Step3. Get mean and std variables only for requirement 2
##Step4. Get discriptive activity names
##Result
- w3.txt: data set merged from train & test data set
- averageALN.txt: data set of average of each variable for each activity
- averageSubject.txt: data set of average of each variable for each subject