Create a generic exception PayutcException

Remove also the error mapping since it is not used. Now all
exceptions will be serialized the same way, and if this is a
PayutcException then the httpcode will be 400, otherwise 500.
Add doctrine DBAL
Use DBAL in Blocked#userIsBlocked
Fix ReadOnlyDatabaseTest class

Ensure the insertion is performed only one time
Remove useless lines
Put tabs in all composer.json
Add samples for UPDATE in User
Merge branch 'master' into exceptions
Merge pull request #148 from trecouvr/fix-rodbtest

Fix ReadOnlyDatabaseTest class
Merge pull request #146 from trecouvr/exceptions

Ok travis a foiré (mais que sur une des deux versions de PHP et c'est encore l'échec de merde, de l'api github...) donc bref il est passé.
Correct typo
Add limit to query result
Merge pull request #147 from trecouvr/doctrine-dbal

Doctrine dbal