Wrong sign in example controller

[Kenji Hata]

applications-linux/scl_example_ctrl/tasks/CTaskOpExample.cpp

line 207 is currently: data_->force_task_ = data_->M_task_ * data_->ddx_ + data_->force_task_grav_;

but should have a minus sign like so: data_->force_task_ = data_->M_task_ * data_->ddx_ - data_->force_task_grav_;

[Samir Menon]

Fixed.

[Samir Menon]

Fixed as of dc1b29675c6fe5b1da1d68d5dc8d5aa48a2fa7ec