add gitignore for java build target path
diff --git a/.gitignore b/.gitignore
index a1c2a23..9875179 100644
--- a/.gitignore
+++ b/.gitignore
@@ -21,3 +21,6 @@
 
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
+
+# Java build target
+target