Merge pull request #1 from jiribroulik/day01

initialize submodule
diff --git a/classes/system b/classes/system
new file mode 160000
index 0000000..198b5b7
--- /dev/null
+++ b/classes/system
@@ -0,0 +1 @@
+Subproject commit 198b5b7459c9f602ded773e966888705d866f6dd