Unify jacobian/tendency naming convention

[juliasloan25]

Is your feature request related to a problem? Please describe.
We have the function imp_tendency!, which calls update_aux!, update_boundary_fluxes!, and compute_imp_tendency! (where the actual tendency computation is done). We also have the explicit analogs.

Similarly, we have tendency_jacobian!, which calls update_aux!, update_boundary_fluxes!, and update_jacobian! (where the actual tendency computation is done).

We should unify our naming so the similarities between these functions are more clear. For example:
update_jacobian -> compute_jacobian
tendency_jacobian -> jacobian