pretty print test-results.edn

Closes #3
Use TEST_ENV_THREAD env var as thread count

When set, the TEST_ENV_THREAD specifies the number of threads to use for
testing.  Defaults to 1.

Closes #4
Add startup form and :no-startup profile

The :no-startup profile can be used to control execution of any block
wrapped in the startup form.
Add unique-name to generate unique names

When naming groups in tests, using unique names allows tests to be run
in parallel.

Closes #5