Qt: add copyrightLabel to aboutdialog.ui
Qt: add copyrightLabel to aboutdialog.ui

- add a new label, which can be updated independently from the whole
  license information stuff
- the benefit is, we don't need to re-translate that whole wall of text
  every year the copyright info changes
- update to the same copyright string we use in the source and in the
  bitcoin-qt.exe meta-data information
- removes an obsolete entry from the ui-file

wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin,wastholm/bitcoin