Update definition of `name` field for matchers after matchers were renamed

The names should be in a human readable form (without the `UT_` prefix and without underscore).

So that object name `ut_be_null` is reported as `be null` in reporter.
Example:
```
  expected (actual value): NULL(varchar2)
  to ut_be_like 'a text'
```
Should be reported as:
```
  expected (actual value): NULL(varchar2)
  to be like 'a text'
```