Add sweep method to Servo.Array objects

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Upgrade servo-lab.js to support continuous servos

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
Add new tinkerkit programs

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
lint nits

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>
rebuild docs/example programs

Signed-off-by: Rick Waldron <waldron.rick@gmail.com>