[8] Review request for 8020708 NLS: mnemonics missing in SwingSet2/JInternalFrame demo

[Alexander Scherbatiy]

Hello,
Could you review the fix:
  bug: https://bugs.openjdk.java.net/browse/JDK-8020708
  webrev: http://cr.openjdk.java.net/~alexsch/8020708/webrev.00

  The fix updates mnemonics for the InternalFrameTitlePane.*Button 
properties
  - Mnemonics are loaded from the *.properties files
  - (&Mnemonic) is added for the localized text that does not contains 
the mnemonics char


Thanks,
Alexandr.