Update DoctrineBundle to use 1.3 stable

Also remove require line on unstable version of dbal, it will come soon
so ok to just use latests stable for now.
[Travis] Update Composer for speed
[Composer] Temporary pin Symfony version to 2.5.x

Avoids strict errors currently with Symfony 2.6.
Bump Symfony requirement to ~2.6

See https://github.com/ezsystems/ezpublish-kernel/pull/1111
Fixed minor typo
Merge pull request #211 from sdaoudi/master

Fixed minor typo
Merge pull request #210 from ezsystems/fix_EZP-23752_sf2.6StrictStandards

Bump Symfony requirement to ~2.6
Merge branch 'master' into extensible_kernel-clean