web: add consent preferences to column view of project preferences page.

[drshawnkwang]

Fixes #2857

Description of the Change
Project Preferences column view now has the consent preferences displayed.

Release Notes
Include consent preferences in the Project Preferences column view.

[drshawnkwang]

@lfield, this is a simple fix for issue #2857

[Rytiss]

Having looked through the code but not having ran it, I believe that while this shows the pref in the column view, it mismatches the number of table cells: consent_show_cols() (/html/inc/prefs_util.inc#L190) has the global $venues but does not use it, so it will only generate a single column, whereas other prefs such as privacy prefs will generate as many columns as there are venues.

Now, consent is a global, venue-spanning option, so it makes sense for it to not be repeated for each venue. However, so as not to break the table layout, colspan param could be applied to the value cell, matching the venue count, in both show_value() and the hardcoded table cell with dashes in consent_show_cols().

venue_show() method also does not generate extra columns, so it is visible how it behaves differently. It should probably be fixed too.

[Rytiss]

Changes requested in a PR comment.

[drshawnkwang]

@Rytiss, the latest comment should fix what you are asking about. I attached a screenshot of the table generated by the newest code. Please evaluate if this is what you are looking for.

[Rytiss]

Looks good, merged.