Common subexpression elimination.

::

 cse(DM e) -> DM
 cse([DM] e) -> [DM]
 cse([SX] e) -> [SX]
 cse(SX e) -> SX
 cse(MX e) -> MX
 cse([MX] e) -> [MX]

Extra doc: https://github.com/casadi/casadi/wiki/L_1cp

Doc source: https://github.com/casadi/casadi/blob/develop/casadi/core/generic_matrix.hpp#L702

Implementation: https://github.com/casadi/casadi/blob/develop/casadi/core/generic_matrix.hpp#L702-L704

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