Added redis-server and memcached to travis.yml file.
Added redis-server and memcached to travis.yml file.

Initially this was just to add the redis-server service to travis-ci,
but when reading that documentation I saw that memcached was no longer
on by default and added that as well.

tedious/Stash,bankiru/Stash,csburton/Stash,AndrewCarterUK/Stash,bankiru/Stash,localheinz/Stash,alawnchen/Stash,andrerom/Stash,graphis/Stash,andrerom/Stash,theUniC/Stash,localheinz/Stash,alawnchen/Stash,tedious/Stash,jaredtking/Stash,csburton/Stash,theUniC/Stash,AndrewCarterUK/Stash,jaredtking/Stash,graphis/Stash