Add sphinx config files
Add cmake files for building docs
Add docs directory to cmake
Remove ALL target from docs
Remove using_tox.rst
add reSt versions of start_guide and start_guide.de
Convert INSTALL.md to reSt
Add install.rst to documentation toc
Update link to install documentation
Remove markdown files
Sphinx is not required for building any more
Test building docs with travis
Merge pull request #220 from fhahn/sphinx-docs

Documentation using sphinx