[newbie] permanent installation of discrete.mac



I succeeded in running the package discrete.mac from
https://github.com/andrejv/discrete.mac/wiki/discrete.mac as follows:
file_search_lisp :  cons("/home/coolens/downloads/andrejv-discrete.mac-18274f7/$$$.{lisp}", file_search_lisp);
file_search_maxima : cons("/home/coolens/downloads/andrejv-discrete.mac-18274f7/$$$.{mac}", file_search_maxima);
load("/home/coolens/downloads/andrejv-discrete.mac-18274f7/logic.mac");

so far so good, I'd now like to avoid having to enter these three lines 
each time I'm going to use the package and Id also prefer not having 
logic.mac in my home-directory. My questions are:
1. What is the default place where to put (the files concerning) logic.mac 
in the  linux-debian tree and how to do that properly.
2. How do I make logic.mac available immediately after starting up maxima
(without having to enter extra commands)

kind regards,
hugo