(Experimental) Add DecentHolograms Support

[TheFlagCourier]

🙃

Brief Description:

An attempt to add support for DescentHolograms, supplementing the already-established HolographicDisplays(EOL) support.

Right now, I have it hooked up as a fall-back/alternative implementation. CellUnderAtttack.drawHologram() will prefer HolographicDisplays over DescentHolograms.

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Changes:

• Update NOTICE file
• Update POM (dependency plumbing and minor fixes.)
• Add a check to FlagWarConfig
• CellUnderAttack:
  • Split out drawHologram into drawHolographicDisplay and drawDescentHologram
  • Add setTimerLineDHAPI() (and related field)
  • Update updateHologram() and destroyHologram()
• Add DescentHolograms as a soft-depend to plugin.yml

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Relevant FlagWar Issue tickets:

closes #313

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• [ ] I have tested this pull request for defects on a server.
• [x] I have supplied users with a copy to test.
  • Test Jar No.1
  • Test Jar No.2

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By making this pull request, I represent that I have read and agree to release my own changes that I have submitted under the terms of the accompanying license (Apache-2.0). I guarantee that these changes are mine and are not encumbered by any other license or restriction to the best of my knowledge.

[TheFlagCourier]

D'oh! Thanks for pointing that out.