Fixing .gitignore.
diff --git a/.gitignore b/.gitignore
index 37366d9..0b28617 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,6 +5,7 @@
 .pydevproject
 .settings
 .javacp*
+.checkstyle
 target
 *.iml
 dependency-reduced-pom.xml