added vibra.py script to test rumbler (taken from kernel)

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
add cpufrequtils

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
improved for new /sys locations defined by device tree kernel 3.15ff

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>