Add a flag for calib_smoother command and apply a setup similar to the one used for stoch_simul command:
- Add auxiliary variables for leaded and lagged exogenous
- Set the cutoff applied to the Jacobian at zero for the static and the dynamic models
Corrects a bug in the way to test for the presence of the global variables
Comment the trend test for a balance growth path => problematic with eLogTrend
Take care of user-supplied function by checking whether mode_compute is numeric

Fixes #508

(cherry picked from commit 8ce11bc8486aa89680837f6a50970e6ffdcd446f)
Merge pull request #510 from FerhatMihoubi/master

Various fixes by Ferhat
Reactivate and fix the test for the balanced growth path.

If the homogeneized equation evaluates to zero, then we skip the
test (otherwise the 2nd derivative of the log is infinite, and the test fails
while it should not necessarily).

Closes #506
Refuse non-stationary endogenous variables in deflators.

It is not clear what we should do in that case anyways.
missing semicolon
fix header to remove compilation warning
preprocessor: move M_.Correlation_matrix and M_.Correlation_matrix_ME to preprocessor #392