Remove under development note.

The plugin has proven to be quite stable

Author: robertpustulka

README.md

@@ -9,8 +9,6 @@
 
 This plugin implements [Single Table Inheritance](https://en.wikipedia.org/wiki/Single_Table_Inheritance) (and hopefully will implement Class Table Inheritance in the future) patterns for CakePHP 3.x ORM.
 
-**NOTE: This plugin is under development! Use it at your own risk**
-
 ## Installation
 
 Using composer: