Albop/egm

[albop]

This branch, adds an endogenous grid method. It requires the yaml file to contain special functions. They are provisionnally called:

• half_transition: compute post states as a function of states and controls
• reverse_state: compute states as a function of post states and controls
• expectation: compute expectation as a function of future states and controls
• direct_response_egm: compute controls in closed form as a function of expectation and post-states

It is not optimized for speed as the various calls to the model functions probably induce a non-negligible overhead.

Function egm should work for any kind of exogenous shock (iid, mc, gdp), but is restricted to 1d space.