Update year in copyright comments

[BronyDust]

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• I've followed the contributing guidelines to the best of my understanding
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PR Description

What type of PR is this? (Check one of the boxes below)

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
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• My change requires a change to the documentation
  • I have updated the documentation accordingly

What does this pull request do?

I just updated year in copyright messages across the app (comments and UI). Thied not to change patch logs or something. But it needs to be rechecked.

[devernay]

Thank you!