enable or disable a module based on name or codepool

### Enable/Disable Module in Declaration

Enable or disable a module in `app/etc/modules/*.xml` by name or codePool:

    $ n98-magerun.phar dev:module:enable [--codepool="..."] moduleName
    $ n98-magerun.phar dev:module:disable [--codepool="..."] moduleName

Examples:

    $ n98-magerun.phar dev:module:enable MyVendor_MyModule
    MyVendor_MyModule: enabled
    
    $ n98-magerun.phar dev:module:disable --codepool="community"
    Disabling modules in community codePool...
    Nexcessnet_Turpentine: disabled
    Mage_Usaepay: disabled
    Aoe_Scheduler: disabled
    ...