typos in comments
Add implementation of virtual function ChLinkUniversal::GetLinkRelativeCoords.
Include header <cmath> for trigonometric functions.
Add calculation of reaction force and torque for the ChLinkUniversal joint.
Add a convenience typedef for ChSharedPtr<ChAsset> , similar to ChSharedBodyPtr in ChBody.h
btConvexHull provides its own implementation of int4 which conflicts with the one found in cuda. Ideally btConvexHull would be inside of a namespace but changing this throughout bullet would be messy. Therefore for now I have renamed the type to bt_int4
Merge branch 'develop' of https://github.com/projectchrono/chrono into develop
Since the unit_IRRLICHT now generates a .dll, then the Python module must copy it in the Python libs dir too
Mitsuba renderer no longer needs to be wrapped in python unit
Merge branch 'develop' of https://github.com/projectchrono/chrono into develop
Merge branch 'develop' of https://github.com/projectchrono/chrono into develop
Fix a problem with unit_MATLAB and VS 2010+ , because the Matlab matrix.h defined a symbol that conflicted
Remove ChLinkLockUniversal -- replaced by ChLinkUniversal.
Fix incorrect sign for the reaction force and torque in a universal joint.

This change of sign is necessary due to the manner in which the Lagrange multipliers are included in the EOM in Chrono:
     ( M * v' - C_q^T * lambda ) = ...
Temporarily increase max number of iterations (speed) during assembly.

When performing assembly, we may not have a good initial guess.  We temporarily increase the maximum number of iterations 5-fold and then restore it to the user-specified value for subsequent analyses.
Add alternative implementation of a revolute joint.

This implementation uses Haug's formulation.  The revolute joint is modeled using 3 spherical constraints and 2 perpendicularity constraints.
Better shield from name pollution: Matlab 2012 for instance caused a trouble with _wassert, now this complete encapsulation of matlab header in namespace should fix the problem.
Fix some warnings when using latest CMake and Python unit
The SWIG wrapping for the Python unit failed because the ChLinkLockHook does not exist anymore, yet it defined the shared pointer wrapper. Fixed.
(forgot this in last commit)