Add smoke tests for important basic/all packages

[Chris Warburton]

Sometimes things break at runtime, e.g. a Firefox update might break
Conkeror, etc.

Since we have packaging in place for these things, we might as well add
some tests to check whether the resulting programs work.

For browsers like conkeror and firefox, we might start a local web
server, open the browser on http://localhost:SomeUniquePort and check
whether the server got a request (e.g. python's simple http server will
spit out messages to stderr when it receives requests).

These just need to be "smoke tests", i.e. checking whether the program
performs some simple task, so that we know it's doing *something* (and
not just crashing on startup, for example).