SDL version of Pyxel will complete in a little more!
Hi, Pyxel users.
New Pyxel with brand new native rendering engine starts working! (not complete yet)
It works at least 5-10 times faster than old version.

Old version:
<img width="478" alt="スクリーンショット 2019-05-04 17 19 39" src="https://user-images.githubusercontent.com/678802/57176652-5793d780-6e95-11e9-9d8a-b0cbb6f2e664.png">

New version (see the performance monitor on left top of the window):
<img width="473" alt="スクリーンショット 2019-05-04 17 18 09" src="https://user-images.githubusercontent.com/678802/57176655-5b275e80-6e95-11e9-82d4-700fd914df94.png">

99% of code of new Pyxel is implemented in C++ with SDL2 and Python wrapper is very thin.
So it will be very easy to transport Pyxel to other platforms and/or languages.
