Closing archive file descriptor after unrar is complete

Hi.
Rar archive file still locked after unrar oparation is complete.
```
ExtractArchive extractArchive = new ExtractArchive();  
extractArchive.extractArchive(rar, destinationFolder); 
```
For example I want to delete downloaded rar archive aftrer unrar but it is not possible because file is locked. Just ``arch.close()`` inside extractArchive() needed