Github doesn't seem to use MP for highlighter tokenization
Github doesn't seem to use MP for highlighter tokenization

MagicPython is still used by Linguist, but the actual syntax
hightlighting seems to be driven by something else now.  Thus, remove
the outdated statement from the README.

Closes: #225

MagicStack/MagicPython,MagicStack/MagicPython,MagicStack/MagicPython