Add ability to rename the title of a luatool that has saved contents.

[dennisjenkins75]

Currently, a luatool's title is either "LuaTool" (when empty) or "Lua Controller at (X,Y,Z)" (or possibly other things for other nodes that it has read from). It would be really handy if we could edit that title ourselves. I have a chest with several luatools in it, with different saved copies of LUAC code, and can't tell them apart, especially if I move LUAC's around in the game; the x/y/z coords become meaningless. I'd like to be able to give them free-form names, like "display driver 2021-05-29-v3" and such.