Hide unlisted videos from channel

[loop-index]

Fix: Hide unlisted videos from channel (#20 and #27)

PR Description:

Unlisted videos no longer show up in channel video list.

Problem:

Unlisted videos are hidden from the front page, but still show up in channel page.

Solution:

Add filter to list function to only show videos that have visibility set to public.

Closes #20

[CLAassistant]

All committers have signed the CLA.