Add comments to justfile commands

Justfile

@@ -1,7 +1,9 @@
 qemu:
+    # Build and run kernel in QEMU
     cargo make qemu
 
 device:
+    # Build and write kernel to an SD Card
     cargo make sdcard
 
 build:
@@ -9,27 +11,34 @@ build:
     cargo make build
 
 clean:
+    # Clean project
     cargo make clean
     rm -f kernel8 kernel8.img
 
 clippy:
+    # Run clippy checks
     cargo make clippy
 
 test:
+    # Run tests in QEMU
     cargo make test
 
 alias disasm := hopper
 
 hopper:
+    # Build and disassemble kernel
     cargo make hopper
 
 alias ocd := openocd
 
 openocd:
+    # Start openocd (by default connected via JTAG to a target device)
     cargo make openocd
 
 gdb:
+    # Build and run kernel in GDB using openocd or QEMU as target (gdb port 5555)
     cargo make gdb
 
 nm:
+    # Build and print all symbols in the kernel
     cargo make nm