/usr/bin/luaotfload-tool is in texlive-luatex 2015.20160320-1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/../share/texlive/texmf-dist/scripts/luaotfload/luaotfload-tool.lua
/usr/bin/../share/texlive/texmf-dist/scripts/luaotfload/luaotfload-tool.lua