[ONOS-7340]: Add 'Last Updated' Date to All TestON Result Wiki Graphs

Change-Id: I73f49a8b9a8c1e255aab7ac74d017b3b74bd29eb
diff --git a/TestON/JenkinsFile/scripts/testCategoryBuildStats.R b/TestON/JenkinsFile/scripts/testCategoryBuildStats.R
index c0211bc..0b4d4b5 100644
--- a/TestON/JenkinsFile/scripts/testCategoryBuildStats.R
+++ b/TestON/JenkinsFile/scripts/testCategoryBuildStats.R
@@ -263,9 +263,12 @@
                 legend.position = "bottom",
                 legend.text = element_text( size = 22 ),
                 legend.title = element_blank(),
-                legend.key.size = unit( 1.5, 'lines' ) )
+                legend.key.size = unit( 1.5, 'lines' ),
+                plot.subtitle = element_text( size=16, hjust=1.0 ) )
 
-title <- ggtitle( title )
+subtitle <- paste( "Last Updated: ", format( Sys.time(), format = "%b %d, %Y at %I:%M %p %Z" ), sep="" )
+
+title <- labs( title = title, subtitle = subtitle )
 
 # Store plot configurations as 1 variable
 fundamentalGraphData <- mainPlot +