Planet phase groundwork laid

[Noobly-Walker]

• Cleaned up phase template to make phased planets look better
• Filled in the black square in the halo template, so the halo can be larger than the planet.
• Doubled size of Pluto and Charon's halos, to make them easier to spot.
• Using autophase.exe, generated or regenerated phase and halo_phase graphics for all planets and moons.
• Created alternate texture for Luna for using with the new phase template. Vanilla texture and halo remains untouched.
• Moved all moon ResourceLocation definitions to Planet.java, pending eventual Moon.java deprecation
• Attempted to re-align all bodies in the solar system so that, when phased, the lit side should more or less point towards the sun. Didn't work.
  • The rotations given should more or less correlate to axial tilt, rounded to the nearest 90°.
• Planet.getUV() calls Planet.getPhase(), which currently returns 0. Someone better at trig than me can probably do better at getting that to work.

[Noobly-Walker]

My vision for this being completed:

• Planet.getPhase() finished. When Mercury and Venus are "on top of" the sun, they will either be full or new. When to the left or right, they will be lit and rotated to give the illusion that sunlight is bouncing off them and reaching Earth.
• Moon.java was, as far as I can tell, only differentiated from Planet.java by phases. The VanillaMoon extension Luna uses could likely extend Planet instead of Moon, without any issue, and Moon.java would get deprecated or removed outright due to being redundant.
• Luna is rotated 90° one way or the other, so that it too gets the illusion that light reflected off of it comes from the sun, instead of some non-existent polar light source.