Build and tests passing: Linux

Herein lies the Boost-ified edition of standalone https://github.com/ned14/outcome. This library was accepted into Boost in January 2018. This repo is generated by script and thus any changes made here will get eaten!

Installation into an older Boost and running the test suite:

cd boost/libs
git clone --depth 1 https://github.com/ned14/boost-outcome.git outcome
cd ..
./b2 headers
./b2 libs/outcome/test cxxflags=--std=c++14