Added asciinema link to README.md

Author: ubaldot

README.md

@@ -1,6 +1,7 @@
 # vim-MarkDown-Extras (MDE)
 
-[![asciicast](https://asciinema.org/a/UbDuIOCSPp1H1F4a7VIcZm5Qj.svg)](https://asciinema.org/a/UbDuIOCSPp1H1F4a7VIcZm5Qj)
+<!-- [![asciicast](https://asciinema.org/a/UbDuIOCSPp1H1F4a7VIcZm5Qj.svg)](https://asciinema.org/a/UbDuIOCSPp1H1F4a7VIcZm5Qj) -->
+<script src="https://asciinema.org/a/UbDuIOCSPp1H1F4a7VIcZm5Qj.js" id="asciicast-UbDuIOCSPp1H1F4a7VIcZm5Qj" async="true"></script>
 
 This plugin adds some spice to the bundled [vim-markdown][3], such as: