Vincent van Hees;
Jairo H Migueles;
Joan Capdevila Pujol;
Jurriaan H. Spaaks;
Added automatic detection of missing suggested packages such as GGIRread when code recognises that they will be needed #786.
Vignettes: instruction expanded about when to install additional R packages #786.
Part 2: minor bug fixed in strategy = 3 and strategy = 5 (now they consider the first ndaywindow which is equal to the max activity level) #796