How to use page: Drop description of the plugin features
How to use page: Drop description of the plugin features

This information is redundant with the feature-set page. Link to this
page instead.

Signed-off-by: Edwin Kempin <d43fb6c98c97e553b671ed9a9318100f1de386e7@google.com>
Change-Id: I35856ff6e4c9821259a829d699a3424dee480b92

GerritCodeReview/plugins_code-owners,GerritCodeReview/plugins_code-owners,GerritCodeReview/plugins_code-owners,GerritCodeReview/plugins_code-owners