Update README.md

Add donation button - to buy new printer if needed

Author: Luc

README.md

@@ -114,4 +114,7 @@ If not, you should have "Watchdog feature was not compiled into this version!" i
 ##Current menu (not up to date):
 Easy: <img src='https://cloud.githubusercontent.com/assets/8822552/4748170/bfa0b7e8-5a69-11e4-80b7-02b9c99fe122.png'>   
 Advanced :  <img src='https://cloud.githubusercontent.com/assets/8822552/4748932/bebab9e2-5a7c-11e4-8fea-cdbe3d70820c.png'>   
-
+***
+##Donation:
+Every support is welcome: [<img src="https://www.paypalobjects.com/en_US/i/btn/btn_donateCC_LG_global.gif" border="0" alt="PayPal – The safer, easier way to pay online.">](https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=VT5LV38N4U3VQ)    
+Especially if need to buy new printer to add FW support.