minor #419 remove old and unnecessary preamble from the README (jrobeson)
minor #419 remove old and unnecessary preamble from the README (jrobeson)

This PR was merged into the 1.4.x-dev branch.

Discussion
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remove old and unnecessary preamble from the README

I'm pretty sure information about Symfony 2.0 and 2.1 is unnecessary anymore. Nor do i think we need to explain why the DoctrineBundle was pulled out of core.

Commits
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945f986 remove old and unnecessary preamble from the README

hacfi/DoctrineBundle,fabpot/DoctrineBundle,hason/DoctrineBundle,OskarStark/DoctrineBundle,fabpot/DoctrineBundle,skafandri/DoctrineBundle,nicolas-grekas/DoctrineBundle,Soullivaneuh/DoctrineBundle,javiereguiluz/DoctrineBundle,OskarStark/DoctrineBundle,hason/DoctrineBundle,gencer/DoctrineBundle,Soullivaneuh/DoctrineBundle,mikeSimonson/DoctrineBundle,nicolas-grekas/DoctrineBundle,mikeSimonson/DoctrineBundle,chrisguitarguy/DoctrineBundle,javiereguiluz/DoctrineBundle,fervo/DoctrineBundle,gencer/DoctrineBundle,chrisguitarguy/DoctrineBundle,skafandri/DoctrineBundle,hacfi/DoctrineBundle,doctrine/DoctrineBundle,fervo/DoctrineBundle