Added Azteeg X3 board.

Marlin/Configuration.h

 // 64 = STB V1.1
 // 65 = Azteeg X1
 // 66 = Melzi with ATmega1284 (MaKr3d version)
+// 67 = Azteeg X3
 // 7  = Ultimaker
 // 71 = Ultimaker (Older electronics. Pre 1.5.4. This is rare)
 // 77 = 3Drag Controller

Marlin/pins.h

 * Arduino Mega pin assignment
 *
 ****************************************************************************************/
-#if MOTHERBOARD == 3 || MOTHERBOARD == 33 || MOTHERBOARD == 34 || MOTHERBOARD == 35 || MOTHERBOARD == 77
+#if MOTHERBOARD == 3 || MOTHERBOARD == 33 || MOTHERBOARD == 34 || MOTHERBOARD == 35 || MOTHERBOARD == 77 || MOTHERBOARD == 67
 #define KNOWN_BOARD 1
 
 //////////////////FIX THIS//////////////
 // #define RAMPS_V_1_0
 
 
-#if MOTHERBOARD == 33 || MOTHERBOARD == 34 || MOTHERBOARD == 35 || MOTHERBOARD == 77
+#if MOTHERBOARD == 33 || MOTHERBOARD == 34 || MOTHERBOARD == 35 || MOTHERBOARD == 77 || MOTHERBOARD == 67
 
   #define LARGE_FLASH true
   
     #define LED_PIN            13
   #endif
 
-  #if MOTHERBOARD == 33 || MOTHERBOARD == 35
+  #if MOTHERBOARD == 33 || MOTHERBOARD == 35 || MOTHERBOARD == 67
     #define FAN_PIN            9 // (Sprinter config)
   #else
     #define FAN_PIN            4 // IO pin. Buffer needed
     #define HEATER_0_PIN       10   // EXTRUDER 1
   #endif
 
-  #if MOTHERBOARD == 33 
+  #if MOTHERBOARD == 33 || MOTHERBOARD == 67
     #define HEATER_1_PIN       -1
   #else
     #define HEATER_1_PIN       9    // EXTRUDER 2 (FAN On Sprinter)
         #define SDSS 53
         #define SDCARDDETECT -1
         #define KILL_PIN 41
-              
+      #elif defined(LCD_I2C_VIKI)
+        #define BTN_EN1 22  //reverse if the encoder turns the wrong way.
+        #define BTN_EN2 7
+        #define BTN_ENC -1
+        #define SDSS 53
+        #define SDCARDDETECT 49
       #else
         //arduino pin which triggers an piezzo beeper
         #define BEEPER 33  // Beeper on AUX-4