fixes: If class \ interface definition exists before the word under the cursor, forbid to generate new class

Before fix(haxe):
![](http://service.crazypanda.ru/v/clip2net/B/5/WUyiJkLGwU.png)

Before fix(as3):
![](http://service.crazypanda.ru/v/clip2net/m/P/Lj3IOtP2ky.png)

After fix(haxe):
![](http://service.crazypanda.ru/v/clip2net/N/N/LnVMkNVoRD.png)
![](http://service.crazypanda.ru/v/clip2net/v/m/jJJJAPqD98.png)
After fix(as3):
![](http://service.crazypanda.ru/v/clip2net/x/d/wqDgvTjm9D.png)
![](http://service.crazypanda.ru/v/clip2net/f/i/GF4MlrWLEQ.png)