Add the current Git version number to the Gerrit page footer

We embed the Git version number in the JavaScript code output by GWT,
so its an integral part of the browser download.  Whatever version of
code the browser is running is what gets displayed in the footer.

Signed-off-by: Shawn O. Pearce <sop@google.com>
diff --git a/appjar/.gitignore b/appjar/.gitignore
index 1c24d2c..327edb0 100644
--- a/appjar/.gitignore
+++ b/appjar/.gitignore
@@ -2,6 +2,8 @@
 /.classpath
 /.project
 /.settings/org.maven.ide.eclipse.prefs
+/src/main/java/com/google/gerrit/client/GerritVersion.properties
+/src/main/java/com/google/gerrit/client/GerritVersion_*.properties
 /gwt_www
 /tomcat
 /hs_err_pid*.log