Add R scripts to plot performance charts

Change-Id: I20d33a47722f515897c79e9e58c49f6391e48eac
diff --git a/.gitignore b/.gitignore
index b044dfd..87ecf80 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,3 +8,4 @@
 *~
 .*
 !.gitignore
+.Rproj.user