On Windows:
Install Python 2.7.9+. Choose the option to add Python to the PATH.
Open cmd.exe and run the following commands:
>>> pip install sphinx
>>> pip install sphinxcontrib-inlinesyntaxhighlight
>>> cd /path/to/MLS-rst-spec
>>> make.bat html
You have built the documentation (with the exception of some LaTeX/math things that can be built by changing the configuration slightly).