[VE][338] New Error Message Suggestion

Here is an error message for #338:

	One of several possible mistakes here:

	1. the entity is misspelled (capitalization is
	important)
	
	2. the closing semicolon of the entity was omitted

	3. "the entity" is actually just an ampersand that
	needs to be encoded as the HTML entity "&".

Hope this helps. Thanks for the wonderful tools!

Mars :)