Always prune __v and add id for GET tasks

[SabreCat]

Previously, our efforts to pare down the database output of fetching tasks resulted in the id field (which copies the internal _id) being excluded when the request included the type=completedTodos query parameter.

Now, logic to add the id and strip the internal __v are moved earlier in the code, executed regardless of whether the user is requesting active tasks or completed To Do's.

[phillipthelen]

Good catch! I missed the return a few lines above my change. Looks good to me