Dan , Micheus ... how to re-submit pull-request ?

[micheus]

... how to re-submit pull-request ?

Is there a really simple way to do this ?

Once the pull request is much more like a reference to your branch, I don't see any problem in you just force a new push over it.

Something important to think about is: your code must be updated/synchronized with the master branch you want it merged. So, update an old pull request can be needed to get it merged to the current master branch.

That's my thought and how I would proceed.
I don't know anything about makefile.git script. I run all git commands by hand - it's my way to learn them.