Add section headings to test console output

i18n tests generate XUnit reports

Move i18n and docs test commands out of tests.rake

Previously, multiple copies of the watchers started from the different
shells would run simultaneously, which left the possiblity of zombie
watchers, increased resource consumption, and incorrect results. This
fixes that problem by only starting a watcher if that same command isn't
already in the process list.

Fixes LMS-499

Rake by default imports all .rake files in the rakelib dir, so we can
use that rather than doing our own import loop.

We used to specify specific rake test tasks so that we could run all of
them even if early ones failed. However, that meant that as new tasks
were added, they weren't being run on jenkins.

Now, there is a facility in the rake scripts so that tests can run using
the test_sh function, which will delay failure until the end of the rake
run, unless the TESTS_FAIL_FAST environment variable is set.

Furthermore, this reorganizes the jasmine test tasks so that we can run
those as part of `rake test` as well.

A better way to compute the hash, that gets the right hash after an install actually installs something.