Make compatible the outputs of the online particle filter with the Dynare...

Make compatible the outputs of the online particle filter with the Dynare routines for presenting results + migrate the Online Particle Filter from nonlinear filters to posterior samplers + make it compatible with commit e4953523 (Efficient_drawing). Now require to create an online option for posterior_sampling_method.

• Document removal of mode_compute=11 as a breaking change in the Wiki.
• Add documentation for the changes/options.