Add new anti-aliased (smooth) font examples + bug fixes

Four new examples have been added to show different methods of rendering
the anta-aliased fonts.  A few minor bugs have been corrected associated
with the font rendering. drawNumber and drawFloat handle fixed width
mono fonts with no digit movement.

Extensions/Smooth_font.cpp

@@ -424,7 +424,7 @@ void TFT_eSPI::drawGlyph(uint16_t code)
 
     uint8_t pbuffer[gWidth[gNum]];
 
-    uint16_t xs = 0;
+    int16_t xs = 0;
     uint32_t dl = 0;
 
     int16_t cy = cursor_y + gFont.maxAscent - gdY[gNum];