Fixes #5985/bz1102120 - Marked content_view_id as required param

Content VIew id is marked as required param in the docs
for the cv filters index call but nothing is enforcing that.
This commit handles that enforcement aspect
fixes #6740 - cleared up enabled text
Merge pull request #4477 from thomasmckay/6740-enabled-label

fixes #6740 - cleared up enabled text
Merge pull request #4473 from parthaa/cv-required

Fixes #5985/bz1102120 - Marked content_view_id as required param