Fixing UserPickerType service configuration
Renaming UserEntityValueConverter to be more verbose (UserIdToStringValueConverter)
Adding ClientManager::find() method
Adding ClientEntityNameDecorator for decorating client entities into string representations
Adding ClientIdToStringValueConverter and tests
Adding client converter and decorator service configuration
Adding ClientPickerType and associated service configuration
Fixing name of UserIdToStringValueConverter test class
Cleaning up implementation of AbstractPickerType, UserPickerType
Adding "tickit_client_picker" field to ProjectFormType, updating tests (currently breaks)