Add option to hide default suggestion about treccanisearch

[giuse94]

Unfortunately, if the default suggestion is turned off, it is replaced by the name of the extension, so we don't gain any advantage.

[giuse94]

Since there's always a default suggestion, we can simplify these lines:

TreccaniSearch/ts/createSuggestions.ts

Lines 72 to 76 in 9380e67

	// Up to six suggestions only are shown in the address bar, including the
	// default suggestion (if set).
	const MaxNumberOfSuggestions = 6;
	// We subtract 1 since the default suggestion is set.
	let numberOfSuggestionsToShow = Math.min(MaxNumberOfSuggestions - 1, json.length);

Just replace 6 with5 and remove - 1 (along with the comment above).

[giuse94]

Unfortunately, if the default suggestion is turned off, it is replaced by the name of the extension, so we don't gain any advantage.

However, the default suggestion can be updated at any time, so we could replace its content (the random hint) with the first suggestion retrieved from the server. I'll give it a try.