Added PdoWriter, Added writer exception to stop PDO exceptions leaking, updated readme, added PdoWriter tests
Merge pull request #71 from warmans/feature/pdo-writer

Added PdoWriter
Switch to SVG for build status tag
Fix converters not being applied to null values
Limit symfony/console version at 2.4
Use Symfony 2.5 ProgressBar Helper + allow option to set verbosity
Merge pull request #73 from WeareJH/symfony-progressbar-helper

Use Symfony 2.5 ProgressBar Helper + allow option to set verbosity
OneToMany Reader - For Merging 2 readers
Merge pull request #78 from WeareJH/one-to-many-reader

One to many reader
Nested itemconverter for recursive arrays.
* Amended docblocks as requested
* Construct param orders changed
* Variable changed to match other pull request.
Forgot to amend test