prevent motor copy. fix #19
make MotorSet.motors immutable, fix #16
fix MotorSet.angle_limits bug, closes #3
decreased timeout to 1, added tools scripts
scripts for linux ftdi support
fix serialio in Linux + test
fix absolute import for p3k
fix scan bug in Linux, fixes #1
robust ping_broadcast
fix for expand_values in MotorSet
deactivate broadcast_ping by default