Refactor download.download
Refactor download.download

search.find_suitable_rock now can't return a table.

robooo/luarocks,luarocks/luarocks,xpol/luavm,xpol/luavm,xpol/luainstaller,robooo/luarocks,keplerproject/luarocks,xpol/luainstaller,keplerproject/luarocks,luarocks/luarocks,xpol/luainstaller,xpol/luarocks,xpol/luavm,tarantool/luarocks,xpol/luarocks,robooo/luarocks,xpol/luarocks,xpol/luainstaller,keplerproject/luarocks,xpol/luavm,robooo/luarocks,tarantool/luarocks,xpol/luavm,xpol/luarocks,keplerproject/luarocks,luarocks/luarocks,tarantool/luarocks