BUG onDemand plugin fixture

Added trim() to decodePath function. Headers X-Include-* comes with a
space so some files are loaded twice. Looks like that depends on a
webserver. nginx has the space.

At the screenshoot you can see boolean values of console.log($.isItemLoaded(jsIncludePath)); and if it was false it displays a path of the script to load. You can see that lib.js was loaded twice (actually 3 times cuz it's also in the HTML).
![screen shot 2013-10-27 at 8 08 22 am](https://f.cloud.github.com/assets/672794/1414754/aebcd23e-3ea6-11e3-97ef-ed076db5da38.png)