X-Clockwork-Requested-With header for lean usage

[eugene-manuilov]

I would like to suggest one small enhancement for the Chrome extension. Is it possible to implement an ability to add custom X-Clockwork-Requested-With header to each request to a server when extension is used? In this case I can run server-side part only when it is required by custom header in a request. Does it makes sense?

[tchiotludo]

@eugene-manuilov : i've implemented this on this pull request : #18
I hope to have some feedback about it from @itsgoingd