move to a single load method

gistfile1.txt

### Before ###
## Doctrine Configuration
doctrine.dbal:
    dbname:   xxxxxxxx
    user:     xxxxxxxx
    password: ~
    logging:  %kernel.debug%
doctrine.orm:
    auto_generate_proxy_classes: %kernel.debug%
    mappings:
        HelloBundle: ~
hello_config: ~

### After ###
## Doctrine Configuration
doctrine:
    dbal:
        dbname:   xxxxxxxx
        user:     xxxxxxxx
        password: ~
        logging:  %kernel.debug%
    orm:
        auto_generate_proxy_classes: %kernel.debug%
        mappings:
            HelloBundle: ~
# hello configLoad() will be called if defined