Here's my PR for the changes discussed in #19823. I decided to leave `_these_` types of italics the way there were because it differentiates the use of italics for emphasis from `*key term*` italics. Otherwise, bolded terms have been changed to italics, and single and double quotes have been changed appropriately, depending on their context (my judgement may not be the best, though).
r? @steveklabnik (congratulations on #19897 being finalized and merged, by the way!)
This commit is an attempt to standardize the use of punctuation and
formatting in "The Rust Programming Language" as discussed in #19823.
- Convert bold text to italicized textcwhen referring to terminology.
- Convert single-quoted text to italicized or double-quoted text,
depending on context.
- Use double quotes only in the case of scare quotes or quotations.
