Disambiguate <emph> tags

[JonathanReeve]

This is an umbrella issue to track these more specific issues:

• Disambiguate <emph> to <foreign> for foreign languages. (Disambiguate <emph> to <foreign> for foreign languages #2)
• Disambiguate <emph> to <title> for titles of works. (Disambiguate <emph> to <title> for titles of works #3)
• Disambiguate <emph> to <said> for direct and indirect speech and thought.
• Disambiguate <emph> to <name> for ships, horses, etc (Disambiguate <emph> to <name> for ships, horses, etc.  #10)