Remove old docs folder.
Add https://github.com/unittest-cpp/unittest-cpp.wiki.git as submodule 'docs'.
Add Documentation, Pre-requisites, and Downloading instructions to main README.
Add link to contributor graph under 'Contributors'.
Incorporate new commits in wiki.
Incorporate latest wiki docs.
Merge pull request #41 from pjohnmeyer/documentationUpdates

Documentation updates from my repository. Further doc updating will be done directly on master.