added gradle automatic build support

hi! i grabbed this the other day and have done a small amount of testing with the project, or, rather, my partner did, by taking ships she had been testing for rotation issues on; it seems to work the same as the 1.7.1 versions does. did similar with the DrugMod mod (by KeeperofMee, who did the Color-Blocks mod) and it seems to be nominally working, or at least items are showing fine in my instance from that mod.

also have created a github with the files at playlaughlovelearn/LisasGradleTemplate since i imagine i'm not the only one who pulls mods and builds them and doesn't want to re-invent the wheel every time.

the files that were moved were because gradle's default Java workspace expects the files there, reduced the amount of unknowns i had to figure out before it was working; i don't think it's a terrible lot of work if you prefer to keep your source files at the same spot, i would be happy to look at that if you would like.

anyhow, so figured i would put in a pull request here and with KeeperofMee so you folks could benefit from it, should you care to have this kind of setup. :) <3