UFO:Alien Invasion Code

* base/textures png crush.

* Reduced filesize of the tex_buildings textures folder by compressing/optimizing the .png files with pngout

* [TEXTURE_.MAP_RESCALE-tex_buildings/floor_se01-0.5-0.5]
* [TEXTURE_.MAP_RESCALE-tex_buildings/floor_se02-0.5-0.5]
* Rescaled all floor_se01 and floor_se02 textures on all map files and prefabs (TODO:repeat this operation in data_source)
* Replaced floor_se01 and floor_se02 textures with 512x512 pixel png versions (were 256x256 before)
* Updated LICENSES

* replaced textures with gpled versions