Add gitignore.
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..3898b7a
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,8 @@
+*.o
+*.sym
+*.asm
+*.lst
+*.lnk
+*.bin
+*.map
+*.ihx