[WIP] [No merge till beta] Add Alliance Chieftan

[jessb321]

Do not merge until at least beta (25th)

Adds the Alliance Chieftan

[jessb321]

Should be right to merge to beta @strideynet

[ghost]

Do you know if the chieftain is Horizons-only? Haven't had time to download and play the beta myself yet. If so, could you add the following to the ship's JSON?

"requirements": {
    "horizons": true
},

Can look at the Beluga or Dolphin files for reference. That should ensure the "Horizons" icon shows up next to the ship's name on the outfitting page (my one and only contribution thus far).

[jessb321]

@joshlcampbell yep, it is horizons only. Will add. Thanks

[ghost]

@willyb321 Awesome :) Thanks