fixes #3751 - new/edit submit buttons now have id

This adds HTML id attributes to all submit buttons created with
submit_or_cancel function. QA engineers requested that.

@omaciel can you test this patch if it is sufficient for you?

It should cover 95 % of all cases. If this works for you and you find some
remaining forms where you want to add id attributes, open another issue and
list all the elements there, I will add the rest manually.

I was unsure where to put a unit/functional test, so I used architectures for
that which works fine.