A few constants where they belong

Marlin/Marlin_main.cpp

     //this is dangerous if a mixing of serial and this happens
     strcpy(&(cmdbuffer[bufindw][0]),cmd);
     SERIAL_ECHO_START;
-    SERIAL_ECHOPGM("enqueing \"");
+    SERIAL_ECHOPGM(MSG_Enqueing);
     SERIAL_ECHO(cmdbuffer[bufindw]);
     SERIAL_ECHOLNPGM("\"");
     bufindw= (bufindw + 1)%BUFSIZE;
     //this is dangerous if a mixing of serial and this happens
     strcpy_P(&(cmdbuffer[bufindw][0]),cmd);
     SERIAL_ECHO_START;
-    SERIAL_ECHOPGM("enqueing \"");
+    SERIAL_ECHOPGM(MSG_Enqueing);
     SERIAL_ECHO(cmdbuffer[bufindw]);
     SERIAL_ECHOLNPGM("\"");
     bufindw= (bufindw + 1)%BUFSIZE;

Marlin/SdFatConfig.h

 #define FILENAME_LENGTH 13
 /** Number of VFAT entries used. Every entry has 13 UTF-16 characters */
 #define MAX_VFAT_ENTRIES (2)
+/** Number of UTF-16 characters per entry */
+#define FILENAME_LENGTH 13
 /** Total size of the buffer used to store the long filenames */
 #define LONG_FILENAME_LENGTH (FILENAME_LENGTH*MAX_VFAT_ENTRIES+1)
 #endif  // SdFatConfig_h