Correct misc build errors

These commits mostly contain very simple rst syntax corrections to resolve some build errors I was getting this morning after performing a fetch upstream. Only big change was the section that was added to the Spanish version of the docs for Volt, which was missing. I tried my best to check each language file and make needed changes to them as needed. 

**NOTE** This pull request does not resolve all the build errors I found. The rest were from references in the API docs, which I understand are auto-generated. I have not played with that yet, so I figured I would play it safe and leave those along, for now.