Update Db.php

This prevents the removeInserted function from re-attempting to remove ids which it has previously failed to remove.
created Symfony connector, added Doctrine to persistent services
fixed running JSON and TAP loggers when they are not expected
added Symfony app to Travis
fixing symfony demo app deployment on travis
Merge pull request #1213 from acdameli/cleanup-db-module-inserted-ids

Update Db.php
printing returned values in console
updated WebDriver download url
updated WebDriver module with PhantomJS docs
Merge branch '2.0' of github.com:Codeception/Codeception into 2.0
trying to reproduce #1212
codecept build command should create corresponding directories. Fixes #1215
fixes #940
small Symfony improv
Symfony 3 dir structure implemented
Fixed Yii2 connector to be compatible with Yii2 master
Symfony2 added config option for debug
Merge branch '2.0' of github.com:Codeception/Codeception into 2.0
generate suite not throwing exception when suite dir exists, as it could be created by 'build' command
updated docs