textures.inc - Skies

### 7.18.2 textures.inc - Skies

Sky pigments:

`Blue_Sky_Map, Blue_Sky`
  Basic blue sky with clouds.
`Bright_Blue_Sky`
  Bright blue sky with very white clouds.
`Blue_Sky2`
  Another sky.
`Blue_Sky3`
  Small puffs of white clouds.
`Blood_Sky`
  Red sky with yellow clouds -- very surreal.
`Apocalypse`
  Black sky with red and purple clouds.
  Try adding turbulence values from 0.1 - 5.0 -- CdW
`Clouds`
  White clouds with transparent sky.
`FBM_Clouds`
`Shadow_Clouds`
  A multilayered cloud texture (a real texture, not a pigment).