README: add container section
README: add container section

barakmich/cayley,deskr/cayley,h4ck3rm1k3/cayley,barakmich/cayley,deskr/cayley,deskr/cayley,h4ck3rm1k3/cayley,cayleygraph/cayley,h4ck3rm1k3/cayley,kortschak/cayley,pombredanne/cayley,sayden/cayley,jzelinskie/cayley,cayleygraph/cayley,barakmich/cayley,sayden/cayley,pombredanne/cayley,pombredanne/cayley,sayden/cayley,h4ck3rm1k3/cayley,pombredanne/cayley,jzelinskie/cayley,jzelinskie/cayley,googlearchive/cayley,kortschak/cayley,barakmich/cayley,kortschak/cayley,deskr/cayley,jzelinskie/cayley,kortschak/cayley,deskr/cayley,h4ck3rm1k3/cayley,googlearchive/cayley,googlearchive/cayley,kortschak/cayley,barakmich/cayley,sayden/cayley,googlearchive/cayley