Remove the Propel book chapter and explain why we do that#5369

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weaverryan merged 2 commits intosymfony:2.3from

javiereguiluz:remove_propel_chapter

Jun 28, 2015

Commits on Jun 8, 2015

Remove the Propel book chapter and explain why we do that
javiereguiluz
committed

Commits on Jun 10, 2015

Fixed issues reported by @xabbuh
javiereguiluz
committed