Use of periodic() Method in Drive Subsystems

[stulewin]

Now that the subsystems are hooked into the scheduler (new base class implementation), these methods will get called. Currently just making updates to driveOdometry object - but should make sure we understand any side effect and handle them as necessary.

[Cal-Hagner]

Making updates to the driveOdometry during the periodic cycle is actually what we want to make trajectories work properly. This may have been at the root cause of our earlier trajectory issues. I don't really see a point in doing odometry updates in another method.