[Development] Split submission

[Samuel Gaist]

Hi,

I just started to split a submission in several patches like Stephen Kelly taught me. 

There's just one thing I forgot to ask him: how should the patches be organized and sent since when broken down (it should be three patches), the last one would only apply once the second patch is applied ? 

The first and second part can be separated (so two different submissions) since they solve two different but related problems (the second being triggered when solving the first).

Also what would be the best/recommended setup git wise ? Should I make a topic branch from my topic branch ?

Thank you