Clang Format

[dteague]

One thing that I've just learned about is clang-format and I think it is a fairly good system that can clear up a lot of these tabs vs space issue we've found from commits as well as making quick fixes to formatting issues. We can base it off other projects like google, webkit, LLVM, etc or even modify them to our taste (eg, i like 4 space, but most styles require only 2 ☹️ )

If you have a strong preference, we can choose on, add it in, and make a commit devoted to running it on all our c++ files

[kdlong]

Sounds good to me, I strongly prefer 4 to 2 spaces. If you can set it up that'd be great

[dteague]

I'll start a PR!