Code simplification, do not pass endo_simul and exo_simul to bytecode through the global structure oo_.

In some cases, for instance for the non linear filters, it helps to reduce this new gstep parameter
to get a positive definite hessian matrix. options_.gstep is now a 2*1 vector. The first element is
the old gstep parameter, the second element is the new gstep parameter. The step defined for the
computation of the hessian matrix is now:

h1=max(abs(x),sqrt(gstep(1))*ones(n,1))*eps^(1/6)*gstep(2);

Force the weights to sum up to one, and not to the number of particles as in WK (Econometrica 2010).

Adds the index of equations (M_.blocksEQU) for a block decomposed model without bytecode option and use this index in resid.m to retrieve the residuals

Return the whole simulated paths instead of only the contemporaneous reaction of the endogenous variables.

Otherwise we can not test the number of periods and we cannot use the previous solution
to initialize the following (stochastic) perfect foresight problem.