Update JGit to 0.9.3.133-gaa09599

This fixes an issue with the default HistogramDiff implementation,
which was marking large unmodified regions as though they were
replaced by the author of a change.

Change-Id: Iec1ec815dce51319a9491e35f8906a6dd10f129e
Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/pom.xml b/pom.xml
index 35afd54..9a4e2c1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -46,7 +46,7 @@
   </issueManagement>
 
   <properties>
-    <jgitVersion>0.9.3.86-g4c7e100</jgitVersion>
+    <jgitVersion>0.9.3.133-gaa09599</jgitVersion>
     <gwtormVersion>1.1.4</gwtormVersion>
     <gwtjsonrpcVersion>1.2.2</gwtjsonrpcVersion>
     <gwtexpuiVersion>1.2.2</gwtexpuiVersion>