Make sed commands clearer
Assorted tidying of Travis config
Follow-on from feedback to PR#26: revert style changes, remove loopback lines
Follow-on from feedback to PR#26: add loopback note to README as suggested
Reorder according to http://docs.travis-ci.com/user/build-lifecycle/
Merge pull request #26 from ucamrc/travisimprovements1

Travisimprovements1