dg : revert last commits as I won't be able to fix everything before

leaving
Revert "dg : some fixes (functor)"

This reverts commit c25745274f596fd0d887efa51a4cafe9deeb72ba.

Revert "dg : functionPrecomputed->functor"

This reverts commit 6039a7ebfc4eb32c682e30338f151e193e54bece.

Revert "fix"

This reverts commit 12b85bf0978ab2706e2290fd53918b114bd89e76.

Revert "dg : introduce functorNumpy"

This reverts commit dbda48a49cc7e78ad341b2655bce2c9dbe03a7d4.