gh437: Fix approve email message
gh437: Fixes for the approve/rejected task emails

We should use task.get_subtitle_version() instead of
task.new_subtitle_version.  With the TED tasks, you never know when
that attribute is actually set.
Fixed attribute error
add tests for checking emails after tasks accepted or sent back.
Merge pull request #689 from jdragojevic/wd-437

add tests for checking emails after tasks accepted or sent back.
gh437: fix user for approval/rejected messages
update the selenium tests, skip the ones for gh-600
skip that test
Merge pull request #698 from pculture/gh-437

Gh 437