Display Page Titles entry/exit reports #1996

Since #1898 we process entry/exit Pages metrics for all Page titles, but do not display them.

Rather than adding 2 new screens similar to the current 'Entry pages' and 'Exit pages' reporting metrics for Page URLs, maybe we
could display the Page Titles metrics in this same screen.

Proposal using the new "related report" feature:

• Below Page Titles report: link to related reports "Exit page titles" and "Entry page titles"
• Below Entry page URLs : link to related "Entry page title"
• Below Exit page URLS: link to related "Exit page title"
• Below "Entry page title" : link to related Page Titles, Entry Page URLs. Idem for "Exit page title"

It is a shame to process this extra data if we don't display it in Piwik. I don't know the best to do this, but we must expose the data in some way in the UI, even if it's just a link in the footer or in the title?

(In [6327]) Refs #1996, fix bug in Actions plugin, filtering for entry/exit pages was not conducted in API, but in the Controller.

Nice fix, nobody noticed this bug yet ;)

added clear "Proposal using the new "related report" feature" in tix description

I've been thinking about where to put these reports, and I think, since there's space in the 'Entry page'/'Exit page' pages, we could just put the reports next to them. What do you think? It would be a lot clearer than using the related reports feature.

Also it would be nice and consistent to have 2 new widget for each Entry page titles and Exit page titles

(In [6361]) Fixes #1996, refs #3137 added entry page titles & exit page titles reports. Fixed issues w/ related reports feature and actions data tables.

(In [6364]) Refs #1996, #3137 fixed some minor issues w/ new entry/exit page titles reports and added logic to related reports feature to modify report header if available.

(In [6365]) Refs #1996, tweaks.

(In [6366]) Refs #1996 all reports with nice name