Updated the READMEs of the plugins

plugins/example_plugin/README.md

@@ -0,0 +1,12 @@
+# Example plugin
+
+This is just a simple example plugin which can be used as a template.
+
+## Building
+
+For building you need: 
+- [wups](https://github.com/Maschell/WiiUPluginSystem)
+- [dynamic_libs](https://github.com/Maschell/dynamic_libs/tree/lib) for access to the functions.
+- [libutils](https://github.com/Maschell/libutils) for common functions.
+
+Install them (in this order) according to their README's. Don't forget the dependencies of the libs itself.