Rebase drake and add handsim support

I had to change some core drake functionality to get the handsim running, and wound up committing those changes to RobotLocomotion/drake. Those changes get pulled in here. Many of the changes aren't DRC-related at all (e.g. Andy's aero changes), but @kuindersma, maybe others will probably want to make sure I didn't accidentally clobber any changes in @Biped or similar locations to had many conflicts.

I tested this drake with mitdrc/master for walking and end effector teleop in simulation and there were no issues.