clang format coding sytle

[Matthias Kretz]

Hi Paul,

On Thursday, November 19, 2015 05:43:27 PM paul elsner wrote:
> when I enable my clang-format plugin and use the format file provided in
> the repo, if applies a lot of formating changes (for example in
> arithmetics.cpp).
> What is the guideline on formating?

Guideline:
Use clang-format for new code and for code that you modify. Ignore clang-
format trying to remove whitespace used for vertical alignment of similar 
neighboring lines. Alignment is very useful for vertical editing...

There's a lot of code in Vc that was written (and formatted) before clang-
format came around. I don't want to clutter history with a huge clang-format 
commit, that's why I prefer to update the formatting as the code evolves.

> Can someone double check if you also the these changes? Maybe my plugin is
> buggy.

I've looked through your last commit on Github and that looks fine.

Cheers,
  Matthias