Topic: oolin(oovars) constraints now are rendered into linear ones

I have committed the following changes: now, if you have some oolin(from some_oovars) constraints in p.c or p.h, they go to general linear constraints Ax <= b, Aeq x = beq (previously they remained as general non-linear constraints c, h). It would be good to make the procedure recursive (i.e. if there are some constraints in the form oolin(oolin(...(oolin(some_oovars),some_other_oovars)...)), render them into linear constraints as well), however, this will be certainly absent in nearest release (I have more important things to be implemented into OO).

Thus, the changes will affect ralg and algencan; they will not affect ipopt, scipy_slsqp, scipy_cobyla, lincher (the solvers doesn't pay attention is it linear or non-linear constraint).

BTW, in future I intend to supply each oofun by possibility to assign desired lb and ub constraints (instead of current situation when constraints must be involved via assigning the ones into p.c and p.h).