allow for .bldr folder to be moved to say app/.bldr

even though i was able to move it with

```
{
    "require": {
        "bldr-io/gush-block": "dev-master@dev"
    },
    "config": {
        "vendor-dir": "app/.bldr/vendor",
        "block-loader": "app/.bldr/blocks.yml"
    }
}
```

it would not load configuration properly:

```
~ bldr b merge                                                                Luiss-MacBook-Pro-3 [10:57:39]


  ______    __       _______   ______
 |   _  \  |  |     |       \ |   _  \
 |  |_)  | |  |     |  .--.  ||  |_)  |
 |   _  <  |  |     |  |  |  ||      /
 |  |_)  | |  `----.|  `--`  ||  |\  \
 |______/  |_______||_______/ | _| `._|



 Building the 'cordoval/matthew-7-12' project
  - Matthew 7:12 project -

 Using the 'merge' profile
  - merge flow for matthew -


Running the gushMerge task
> merge flow




  [Exception]
  No task type found for gush:pull-request:merge.


```
to write a reasonable test, if we don't do this, then the new ContainerBuilder() part becomes a nightmare to test.