Moved LCD initialization out of constructor

Since the class "MainMenu" was used within a static variable the
initialization of the object (constructor call) was done before Arduino
library startup. It always caused a crash when using AVRStudio with
JTAG debugger (caused from calling the LCD initialization / the lot of
I/O work / the stack used during this calls). By moving the LCD_INIT
out of the constructor and using an explicit call inside of Arduino
setup() implementation immediately fixed all problems and the JTAG
debugger runs fine.

Marlin/Marlin.pde

@@ -300,6 +300,8 @@ void setup()
   st_init();    // Initialize stepper;
   wd_init();
   setup_photpin();
+  
+  LCD_INIT;
 }