Merge pull request #371 from rattoma/master

bug fixes for GSA tools
Deals with empty values in csv file, removed a useless test
Minor simplification and improvements
Bug fix in steady state solver
reporting: @section: adjust spacing
reporting: @graph: write title directly in latex file (as opposed to Matlab plot).

If you don't do this, the title will be centered over the plot (not including YTickLabel width) as opposed to within the cell. This can be weird if you have one table in the section as the plot title will not center with the page title.
Consider the case of non available variable in the csv file
Merge pull request #373 from FerhatMihoubi/master

2 requests
fixing missing increment of index in unfold3, unfold21, unfold12
adding the constant (steady state + effect of future uncertainty) to
the simulated series with 3rd order approximation
Reset oo_.{exo_}steady_state to zero before endval

This is necessary to enforce the documented behavior which says that, if a
variable is not given a value in the endval block, a zero value is assumed.
Fix handling of auxiliary variables in endval block
fix typo
fix dynare++ build on OS X
Fix unfold for third order pruning
Merge pull request #369 from JohannesPfeifer/master

Bugfix in third order perturbation
reporting: @graph: avoid legend crash on octave
reporting: @graph: add option to turn legend box on or off
Implement Andreasen et al. 2013 pruning at order

Implements and documents the Andreasen et al. 2013 pruning at order=3
and sets it as the default at this order. Michel's pruning based on the
approximation of the forecast function has been assigned the option
pruning_forecast_approximation. The preprocessor-interface still needs
to be added for this option. Moreover, more documentation/a reference
what this option does is needed. At a later point, we might change the
default to Michel's approach.
Add unit test for order=3

The unit test uses the policy rules of Fernandez-Villaverde et al.
(2011)'s "Risk matter" derived from Mathematica to compare them to the
Dynare matrices. If the policy functions differ by more than 1e-9, an
error is produced.