X - table that binds X_train.txt and X_test.txt
Subject - table that binds subject_train.txt and subject_test.txt
Y - table that binds subject_test.txt and y_test.txt
features - table from features.txt
keep - finds features that include "mean" or "std"
ActivityNames - table from activity_lablels.txt
CleanData - table that binds Subject, X & Y - with lower case and appropriate labels.
result - independent tidy data set with the average of each variable for each activity and each subject.