Clarify inconsitencies

@z @pksunkara Please review and merge. This PR addresses: https://trello.com/c/RC0AC7HR/2187-misc-mson-spec-updates
I was thinking the same, however strictly speaking paragraph here would be meant in the sense of Markdown (or HTML `<p>`) paragraph. As we want to move away from expecting users some knowledge of Markdown ([Internal Ref](https://trello.com/c/7EaKdvJG/80-do-not-expect-upfront-markdown-knowledge)) I would say the term "text" is used here properly.