Related to #1935

Fixes crashes in model_info with differentiate_forward_vars

Also add a test with dseries but with bare shocks/endval.

Prevents crashes with smoothed_state_uncertainty option if MCMC smoother is run after classical one

Before, the PKF would be triggered

Modification of the mod-file to call the online sampler with posterior_sampling_method instead of mode_compute=11.

[skip ci]

Should have been removed in b70d99d1.

Ref. #1859

Removes unused prior_analysis_endo_var_list option

Incidentally:
– fix a bug where path for endogenous after failure to converge was not centered
– ensure that sim1_linear.m is actually tested, by adding a test for
  linear_approximation + stack_solve_algo=0

Ref. #1859

⇒ Generated pseudo-random numbers will not change if we add new unit tests.

One input argument is required

Closes #1932

- Remove globals
- Remove unused code paths
- support steady_state_model
- support contemporaneous_correlation
- support TeX option

provide alternative irreversible investment model that uses leads and lags in #declarations, as allowed by 4f6344e6 (see also #1929).
check consistency with results of the original model

Closes: #1929

See #1920

Ref. #1859

In particular, adapt the manual and the testsuite.

Fix `simult_.m` to call specialized simulation codes for order <= 3 instead of `k_order_simul` whenever possible

The test condition was incorrect (though this was probably harmless).

Also the error message related to oo_.dr.ghu was incorrect.

Closes: #1721

The initial guess was set to the solution, so the algorithms would really be
tested.