Testsuite updates including integration with travis-ci.org

The main purpose of this pull request is integration with the travis-ci.org continuous integration service. However, there are some other small fixes and improvements along way including:
 
 - pulled in automake 1.14 tap-driver.sh to drive tests (as seen from #45)
 - simple conversion of `spellcheck` test to TAP output (and additionally check for `aspell`)

Travis itself seems to be very well integrated with github, in fact there should be a build test for
this (and future) pull requests at

  https://travis-ci.org/flux-framework/flux-core

You can also go to travis-ci.org and sign in with your GitHub credentials to get testing on your own fork of the flux-core repo. For example, mine is at

   https://travis-ci.org/grondo/flux-core

The travis-ci.org service is limited in that it only supports ubuntu-12.04 vms, but for now it is much better than nothing at all.