Change default .scss-lint.yml location

Threw my name in there for good measure :hankey: 
Tried it and it didn't really work
But from what I can see on my env when we actually try to run 
```
bundle exec scss-lint -c /Users/user/projects/my-project/node_modules/grunt-scss-lint/tasks/.scss-lint.yml app/main.scss
```
it fails with `No such file or directory - /Users/user/projects/my-project/node_modules/grunt-scss-lint/tasks/.scss-lint.yml`

Even if I specify 

```
bundle exec scss-lint -c node_modules/grunt-scss-lint/tasks/.scss-lint.yml app/main.scss
```
As suggested by original change it still doesn't work, fails with same error (different path)

The only thing that managed to work is 
```
bundle exec scss-lint -c .scss-lint.yml app/main.scss
```

Also tried this on scss-lint 0.28.0 and 0.30.0, got a bit different error, but essentially same meaning of can't find config file.