A quick add guide page.

Added a quick add guide page that asks for the name of the guide and the author id. This is to make population of my own database easier, but I know a bare minimum of RoR, so might not be ideal and needs expanding.
I think this might be a slight mistake on git's diff. Have a look at the code, [it's still there](https://github.com/simonv3/OpenFarm/blob/new-guides/app/views/guides/show.html.erb#L9).