add small matrix/vector library working with simdwrappers + small additions to zipping

1. matrix library with compiletime loop unrolling that works well with simdwrapper.
   most of the credit goes to @ahennequ @graven and Florian Lemaitre.
   We may need to enable a higher inline limit to take full advantage of the inlining that unwind can yield.
2. small additions to simdwrappers (+= -= ...)
3. made zips work with boost::combine and structured bindings for zips
4. until now, proxies could just have the name "proxy", now its an argument to the macro