Added a message warning mencoder is not installed when making an AVI

zsnes/src/gui/gui.asm

@@ -1548,6 +1548,42 @@ LOADDir:
     call Change_Dir
     ret
 
+guimencodermsg:
+    xor ebx,ebx
+    mov ecx,256
+.a
+    mov byte[pressed+ebx],0
+    inc ebx
+    dec ecx
+    jnz .a
+    mov byte[pressed+2Ch],0
+.again
+    GUIBox 43,75,213,163,160
+    GUIBox 43,75,213,75,162
+    GUIBox 43,75,43,163,161
+    GUIBox 213,75,213,163,159
+    GUIBox 43,163,213,163,158
+    GUIOuttext 52,96,guimencodert1,220-15
+    GUIOuttext 51,95,guimencodert1,220
+    GUIOuttext 52,134,guimencodert2,220-15
+    GUIOuttext 51,133,guimencodert2,220
+    call vidpastecopyscr
+    call GUIUnBuffer
+    call DisplayBoxes
+    call DisplayMenu
+    call JoyRead
+    cmp byte[pressed+39h],0
+    jne .pressedokay
+    jmp .again
+.pressedokay
+    ret
+
+SECTION .data
+guimencodert1 db ' MENCODER iS MISSING : ',0
+guimencodert2 db ' PRESS SPACE TO CONTINUE',0
+
+section .text
+
 guifirsttimemsg:
     xor ebx,ebx
     mov ecx,256