Add a simplification version flow in Spanish

Hi @andresmoschini I made a document that contains the explanation "Create branch", "Commit" and "Merge" in Git/TFS flow.

A preview is available at: http://federicocroce.github.io/makingsense.github.io/migration-to-git/4-flows/dp-flow-in-spanish/dp-flow-in-spanish.html
I am not sure about it, the merge checkin message should be related with the changes done.