Added Leonardo to hardware table #224 #281

Author: z3t0

README.md

@@ -33,6 +33,7 @@ We are open to suggestions for adding support to new boards, however we highly r
 | [ATtiny84](https://github.com/SpenceKonde/ATTinyCore)                    | **6**               | **1**             |
 | [ATtiny85](https://github.com/SpenceKonde/ATTinyCore)                    | **1**               | **TINY0**         |
 | ATmega8                                                                  | **9**               | **1**             |
+| Atmega32u4                                                               | 5, 9, **13**        | 1, 3, **4**       |
 | ATmega168, ATmega328                                                     | **3**, 9            | 1, **2**          |
 | [ATmega1284](https://github.com/MCUdude/MightyCore)                      | 13, 14, 6           | 1, **2**, 3       |
 | [ATmega164, ATmega324, ATmega644](https://github.com/MCUdude/MightyCore) | 13, **14**          | 1, **2**          |