Markdowned readme

README.md

@@ -31,6 +31,7 @@ By default, the system is configured for the Max32 board.
 To select another target board, edit a top-level user-specific Makefile called "Makefile.user"
 and set a TARGET value:
 
+```Makefile
 TARGET = $(UBW32)          # for the UBW32 board with USB console
 TARGET = $(UBW32UART)      # for the UBW32 board with UART console
 TARGET = $(UBW32UARTSDRAM) # for the UBW32 boars with UART console and 8MB SRAM ramdisk
@@ -49,14 +50,14 @@ and set a TARGET value:
 TARGET = $(FUBARINO)       # Fubarino SD board
 TARGET = $(FUBARINOBIG)    # Fubarino SD board with 8MB SRAM RAMDISK
 TARGET = $(MMBMX7)         # MMB MX7 board
-
+```
 
 You can also change a desired filesystem size and swap area size,
 as required.  Default is:
-
+```Makefile
 FS_KBYTES   = 16384
 SWAP_KBYTES = 2048
-
+```
 To compile the kernel and build a filesystem image, run:
 
 ```shell