following our convention for env var naming, `window.cas` should be renamed to `window.cat` example: https://github.com/src-d/code-annotation/blob/master/public/index.html#L31
following our convention for env var naming,
window.casshould be renamed towindow.catexample: https://github.com/src-d/code-annotation/blob/master/public/index.html#L31