Refactoring flow examples

[Stefano Mazzocchi]

Ovidiu did a great job showing how the flow could be well integrated 
into complex publishing pipelines with the samples we have today, but I 
think this is scaring away people that have to simply understand how 
things work.

Also, those samples are now dependent on the presence of the 
documentation in the context, which is not to be assumed since it can be 
excluded from the build independently from the samples.

Moreover, documentation is contained in the samples, but it should live 
in the real documentation.

So, would anybody mind if I:

- refactor the flow samples to make them easier to understand from newbies

- remove dependencies on context://docs

- move the flow documentation into the real documentation

thoughts?

Stefano.