Reset ManagerState's draw color after Font.drawBox

Font.drawBox leaves the caller's color at white; every other screen
resets to black right after calling it, but ManagerState.lua's draw()
and drawOverlay() never did. That's invisible on the vanilla tile font
(tile glyphs are black-on-transparent regardless of color) but renders
fully invisible white-on-white text once a mod's TTF font is active.

src/mods/ManagerState.lua

@@ -1297,6 +1297,7 @@ function ManagerState:drawOverlay()
   love.graphics.rectangle("fill", 2 * 8, ty * 8, 16 * 8, th * 8)
   love.graphics.setColor(1, 1, 1, 1)
   Font.drawBox(2, ty, 16, th)
+  love.graphics.setColor(0, 0, 0, 1)
   for i, line in ipairs(lines) do
     drawTruncated(line, 4 * 8, (ty + i) * 8, 14)
   end
@@ -1325,6 +1326,7 @@ function ManagerState:draw()
   love.graphics.rectangle("fill", 0, 0, 160, 144)
   love.graphics.setColor(1, 1, 1, 1)
   Font.drawBox(0, 0, 20, 18)
+  love.graphics.setColor(0, 0, 0, 1)
   Font.draw(self.banner or Strings("MOD MANAGER"), 16, 8)
   if self.screen == "list" then
     self:drawList()