* Submitting MODX logo
MODX is a popular open source PHP CMS. Its logo is also found in
FontAwesome, seems like it would be great for it to have
* Updated devicon.json and modx svg color
* Fixed issues reported by svg-checker bot
Co-authored-by: JP DeVries <mail@devries.jp>
Co-authored-by: Clemens Bastian <8781699+amacado@users.noreply.github.com>
