Add 4 DPF made plugins (#167)

* Add 4 DPF made plugins

* wooops

README.md

@@ -30,6 +30,10 @@ List of plugins made with DPF:<br/>
  - [DragonFly-Reverb](https://github.com/michaelwillis/dragonfly-reverb)
  - [Wolf-Shaper](https://github.com/pdesaulniers/wolf-shaper) and [Wolf-Spectrum](https://github.com/pdesaulniers/wolf-spectrum)
  - [YK Chorus](https://github.com/SpotlightKid/ykchorus)
+ - [Ninjas2](https://github.com/rghvdberg/ninjas2)
+ - [String-machine](https://github.com/jpcima/string-machine)
+ - [Rezonateur](https://github.com/jpcima/rezonateur)
+ - [QuadraFuzz](https://github.com/jpcima/quadrafuzz)
 
 
 Plugin examples are available in the `example/` folder inside this repo.<br/>