LibGfx: Improve tie-breaking in Typeface::get_font

Add two new members to Font::AllowInexactMatch: Larger and Smaller.
This allows callers of FontDatabase::get to specify if they want to
prefer a larger or smaller font in the event of a tie.

Userland/Libraries/LibGfx/Font/Font.h

@@ -148,6 +148,8 @@ public:
     enum class AllowInexactSizeMatch {
         No,
         Yes,
+        Larger,
+        Smaller,
     };
 
     virtual NonnullRefPtr<Font> clone() const = 0;