minor #669 Use the new "json" type from DBAL 2.6 (javiereguiluz)
minor #669 Use the new "json" type from DBAL 2.6 (javiereguiluz)

This PR was merged into the master branch.

Discussion
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Use the new "json" type from DBAL 2.6

This partially fixes #620 and it's based on #659.

Commits
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189083f Use the new "json" type from DBAL 2.6

TomasVotruba/symfony-demo,voronkovich/symfony-demo,symfony/symfony-demo,yceruto/symfony-demo,TomasVotruba/symfony-demo,voronkovich/symfony-demo,javiereguiluz/symfony-demo,javiereguiluz/symfony-demo,bocharsky-bw/symfony-demo,bocharsky-bw/symfony-demo,TomasVotruba/symfony-demo,yceruto/symfony-demo,symfony/symfony-demo,yceruto/symfony-demo,Codeception/symfony-demo,symfony/symfony-demo,javiereguiluz/symfony-demo,bocharsky-bw/symfony-demo,Codeception/symfony-demo,Codeception/symfony-demo,voronkovich/symfony-demo