run_analysis.R that does the following. *1.Merges the training and the test sets to create one data set. *2.Extracts only the measurements on the mean and standard deviation for each measurement. *3.Uses descriptive activity names to name the activities in the data set *4.Appropriately labels the data set with descriptive variable names. *5.From the data set in step 4, creates a second, independent tidy data set with the average of each variable for each activity and each subject.