Add gwt-unitCache to .gitignore

Change-Id: I2a6ad669daab2a92bce6561795ec4cb61628e101
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
diff --git a/.gitignore b/.gitignore
index 78e784d5..b979660 100644
--- a/.gitignore
+++ b/.gitignore
@@ -13,3 +13,4 @@
 /buck-out
 /local.properties
 *.pyc
+/gwt-unitCache