HELP - Black screen on XT1060 5.1

Ok, I dun goofed. Phone was working fine but I tried to add a line to build.prop and now the phone will show the boot logo but then goes black. I made a copy of the file first and tried putting the old one back with the TWRP file manager, but it's still doing the same thing.

I need help with this fast, my gf is going to kill me if I don't get he phone working again soon. :/

Can someone post a flashable zip of the 5.1 build.prop please. I'm just assuming this will fix it. I've tried extracting the system.img to get it but I obviously don't know what I'm doing.

Thanks