Fix #441 Canvas::DrawText() (#442)

Fix for Canvas::DrawText() draws nothing if the start coordinate is out
of bounds.

src/ftxui/dom/canvas.cpp

@@ -802,6 +802,7 @@ void Canvas::DrawText(int x,
                       const Stylizer& style) {
   for (const auto& it : Utf8ToGlyphs(value)) {
     if (!IsIn(x, y)) {
+      x += 2;
       continue;
     }
     Cell& cell = storage_[XY{x / 2, y / 4}];