#966 Ruleset name doesn't get updated when import ruleset by copy

[Amit Arora]

1. Create a ruleset.xml file having custom rules and also add ruleset name in this file to say 'AB Ruleset'
2. Import that ruleset.xml from PMD UI by clicking Import Ruleset button present in Windows > Preferences > PMD > Rules Configuration
3. A new window open asking for path of ruleset file, click on 'Import by Copy' check box and browse for the file 'ruleset.xml'
4. The rules will be imported successfully and name of ruleset will be shown as 'pmd-eclipse'. It should be 'AB Ruleset' which has been specified in ruleset.xml.
   If rules are imported by reference, then it is showing the correct ruleset name, but import by copy is not showing correct one. It should show the correct ruleset name for both cases.