1.8.0 for Towny 0.97.3.0+.

[LlmDl]

Major refactor of entire codebase. Dropped BetterTownyWars support. Support for Towny 0.97.3.0+. New Permission Node: townyflight.nationtowns

• Grants the ability to fly only in Towns which are in your Nation.
• Closes #47.