SC.Record.refresh does not work

Calling `refresh` on a SC.Record object does not actually refresh the record.

This has to do with line 290 of `lib/system/record.js`.  If refresh is called with no arguments or with `recordOnly = false`, the statement:

```
if (recordOnly || (none(recordOnly) && none(prKey)))
```

will _always_ evaluate to false.

`none(recordOnly)` should be removed.
