Add japanese language support

diff --git a/lang/jp.lua b/lang/jp.lua
new file mode 100644
index 0000000..71c1f63
--- /dev/null
+++ b/lang/jp.lua
@@ -0,0 +1 @@
+SafeAddString(ART_STABLE_MASTER_CAPTION, "親方", 1)
\ No newline at end of file