Don't vendor minified Chart.js

The filename is titlecased because that's how it came from the vendor,
and we're not touching it.

app/assets/javascripts/application.js.coffee

@@ -23,7 +23,7 @@
 #= require raphael
 #= require g.raphael-min
 #= require g.bar-min
-#= require chart-lib.min
+#= require Chart
 #= require branch-graph
 #= require ace/ace
 #= require ace/ext-searchbox