Fixed some wording

Added missing use statement.

ensure lines are aligned right:
```
 7
 8
 9
10
11
12
...
```

Fixes #373

fixes #429

\yii\rbac\DbManager::isAssigned() signature fix

[READY] RBAC DbManager fixes

https://github.com/yiisoft/yii2/commit/a6c251d2ab6d222b5318cc7fa21eb3791a296c62#commitcomment-3291785

Removed dot in path

- update composer json to chosse right path
- set vendorPath in application config if not default

issue #418