Add: Board for Vellemann K8200 (derived from 3Drag)

## Add: Board for Vellemann K8200 (derived from 3Drag)

* Boards.h: updated comment for board 3Drag - K8200 removed
* Boards.h: added `BOARD_K8200` with ID 78

* language.h.: machine name and firmware URL for new board

* pins.h: added `K8200` to any `#if` with `3Drag` and corresponding
comments

Marlin/boards.h

 #define BOARD_ULTIMAKER         7    // Ultimaker
 #define BOARD_ULTIMAKER_OLD     71   // Ultimaker (Older electronics. Pre 1.5.4. This is rare)
 #define BOARD_ULTIMAIN_2        72   // Ultimainboard 2.x (Uses TEMP_SENSOR 20)
-#define BOARD_3DRAG             77   // 3Drag Controller / Vellemann K8200 Controller
+#define BOARD_3DRAG             77   // 3Drag Controller
+#define BOARD_K8200             78   // Vellemann K8200 Controller (derived from 3Drag Controller)
 #define BOARD_TEENSYLU          8    // Teensylu
 #define BOARD_RUMBA             80   // Rumba
 #define BOARD_PRINTRBOARD       81   // Printrboard (AT90USB1286)

Marlin/language.h

 #elif MB(3DRAG)
   #define MACHINE_NAME "3Drag"
   #define FIRMWARE_URL "http://3dprint.elettronicain.it/"
+#elif MB(K8200)
+  #define MACHINE_NAME "K8200"
+  #define FIRMWARE_URL "https://github.com/MarlinFirmware/Marlin"
 #elif MB(5DPRINT)
   #define MACHINE_NAME "Makibox"
   #define FIRMWARE_URL "https://github.com/MarlinFirmware/Marlin"

Marlin/pins.h

 * Arduino Mega pin assignment
 *
 ****************************************************************************************/
-#if IS_RAMPS || MB(3DRAG) || MB(AZTEEG_X3) || MB(AZTEEG_X3_PRO)
+#if IS_RAMPS || MB(3DRAG) || MB(K8200) || MB(AZTEEG_X3) || MB(AZTEEG_X3_PRO)
 #define KNOWN_BOARD 1
 
 //////////////////FIX THIS//////////////
 // #define RAMPS_V_1_0
 
 
-#if (IS_RAMPS && !MB(RAMPS_OLD)) || MB(3DRAG) || MB(AZTEEG_X3) || MB(AZTEEG_X3_PRO)
+#if (IS_RAMPS && !MB(RAMPS_OLD)) || MB(3DRAG) || MB(K8200) || MB(AZTEEG_X3) || MB(AZTEEG_X3_PRO)
 
   #define LARGE_FLASH true
 
-  #if MB(3DRAG)
+  #if MB(3DRAG) || MB(K8200)
     #define X_STEP_PIN         54
     #define X_DIR_PIN          55
     #define X_ENABLE_PIN       38
     #define FAN_PIN            4 // IO pin. Buffer needed
   #endif
 
-  #if MB(3DRAG) || MB(RAMPS_13_EEF)
+  #if MB(3DRAG) || MB(K8200) || MB(RAMPS_13_EEF)
     #define FAN_PIN            8
   #endif
 
   #endif
 
 
-  #if MB(3DRAG)
+  #if MB(3DRAG) || MB(K8200)
     #define HEATER_0_PIN       10
     #define HEATER_1_PIN       12
     #define HEATER_2_PIN       6
   #if MB(RAMPS_13_EFF) || MB(RAMPS_13_EEF)
     #define HEATER_BED_PIN     -1    // NO BED
   #else
-    #if MB(3DRAG)
+    #if MB(3DRAG) || MB(K8200)
       #define HEATER_BED_PIN     9    // BED
     #else
       #define HEATER_BED_PIN     8    // BED
 
       #endif
 
-      #if MB(3DRAG)
+      #if MB(3DRAG) || MB(K8200)
         #define BEEPER -1
 
         #define LCD_PINS_RS 27
 #define TEMP_2_PIN          -1
 #define TEMP_BED_PIN        1    // MUST USE ANALOG INPUT NUMBERING NOT DIGITAL OUTPUT NUMBERING!!!!!!!!!
 
-#endif // RAMPS_13_EFB || RAMPS_13_EEB || RAMPS_13_EFF || 3DRAG
+#endif // RAMPS_13_EFB || RAMPS_13_EEB || RAMPS_13_EFF || 3DRAG || K8200
 
 // SPI for Max6675 Thermocouple
 
   #define MAX6675_SS       66// Do not use pin 49 as this is tied to the switch inside the SD card socket to detect if there is an SD card present
 #endif
 
-#endif // RAMPS_OLD || RAMPS_13_EFB || RAMPS_13_EEB || RAMPS_13_EFF || 3DRAG
+#endif // RAMPS_OLD || RAMPS_13_EFB || RAMPS_13_EEB || RAMPS_13_EFF || 3DRAG || K8200
 
 /****************************************************************************************
 * Duemilanove w/ ATMega328P pin assignment