Added backward/forward/midpoint options to traj opt w/contact.
Added case 15 to snoptInfo.
Merge branch 'drake-origin/master'
Merge branch 'drake-origin/master'

Conflicts:
	solvers/trajectoryOptimization/ContactImplicitTrajectoryOptimization.m
Fixes related to falling brick test.
adding angle average util function
use angleAverage in pelvis motion control block
logic improvelent (handles case when some link_constraints have dtraj, but others don't)
adding cpp angleAverage function
pelvis cpp controller uses angleAverage
fixed variable not defined bug
adding use_mex=2 to body/pelvis motion controllers
adding a walking test mex unit test
Merge pull request #265 from mposa/master

Added integration method support to contact traj opt, updated brick test case.
moved angleAverage to drakeUtil
Merge pull request #266 from kuindersma/add-angle-average

Add angleAverage
mex for desired individual support surface cops
Extracted out function that computes individual CoPs.
* created and thoroughly tested resolveCenterOfPressure function, which computes the cop and normal torque given wrench exerted and contact plane
* created and tested individualCentersOfPressure, which computes desired COPs at each foot given QP controller solution
* started to update the C code based on these changes.
Mex for individualCentersOfPressure. WIP.