Added a note about SKIP_MD5SUM environment variable to manual-tests runner.
Added a note about SKIP_MD5SUM environment variable to manual-tests runner.

jeremysalwen/Ecasound-LV2,jeremysalwen/Ecasound-LV2,jeremysalwen/Ecasound-LV2,jeremysalwen/Ecasound-LV2,jeremysalwen/Ecasound-LV2