I would change the `-d ../.git` check into a `NO_GIT != 1` check, and then set `NO_GIT` in `Make.inc`.  That way, we can also wrap the git submodule stuff in a similar if statement, and we get two birds with one stone.

When setting `NO_GIT` in `Make.inc`, we want to make sure that it is forced to true when `.git/` does not exist (or the `git` executable doesn't exist).  We also want to make sure that the user can set it if they desire.