bugfix: need to escape `$` in Makefiles
don't print runtime paths when running from Travis
restore end-of-patch marker for later automatic fetching of differences
generally don't install recommended apt packages
Merge pull request #20 from krlmlr/bugfixes

minor bugfixes
Merge pull request #21 from krlmlr/no-recommends

generally don't install recommended apt packages
get rid of the paths of runtimes in the output; write them in messages instead

this makes travis ci check cleaner