* Changed "index" to be more similar to the README (#1708).
* Fixes numerous issues like missing documents, syntax errors, etc (#1829, #432).
* Mention all docs in "contents.rst" so it's easier for users to locate (#1112).
* Add doc generation and checking to Travis and AppVeyor, to avoid re-introducing errors.
Fixes#432, Fixes#1112, Fixes#1708, Fixes#1829
Since 'py.test --help' shows --trace-config as an option (and not
--traceconfig) even though both forms are accepted I assume --trace-config is
the preferred form and should therefore be used in the documentation.