Alt text requirement not documented clearly #299
Description
As a beginner using Eleventy (having forked the base-blog repo) I spent a long time trying to debug why my images were being rendered to the site with the wrong paths, failing to realise that they would render correctly if I added alt text.
Afterwards I noticed that it is mentioned only way down in the description for htmlOptions as a single line commented '// required'.
Have I understood the issue correctly? If so, how can the requirement be documented more clearly? I also think an error or warning message should be printed to notify the user when the alt text is missing and why this leads to a broken image.