Explicitly disabled usage of Parameter class in the OCP solvers...

... as well as in the integrators. Users should use the OnlineData
class.
Update export_nlp_solver.cpp
Fixed #77
Fixed #76
Merge pull request #78 from ferreau/master

Update export_nlp_solver.cpp
Merge branch 'master' of github.com:acado/acado
Merging 453dd9ec191fe87048ff2ad42627506e2a8035a0