Improve output for script downloads and cleanup sti tests.

Move the sti test images to tests/images and remove sti/contrib
Enhance contrib/test script to run and debug all types of tests.
Merge pull request #210 from pmorie/sti

Improve output for script downloads and cleanup sti tests.
Remove extra HTTP headers from index.html in busybox-http-app
Merge pull request #214 from mfojtik/busybox_html

Merged by openshift-bot
Make contrib/test run unit tests by default
Merge pull request #215 from pmorie/sti

Make contrib/test run unit tests by default