Use format_metrics instead of showRawMetrics in visitor map JS. This means getting numeric values from Piwik and formatting in JS, instead of getting intermediate metrics, calculating numeric metrics and then formatting in JS.

Fix regression in API.getProcessedReport, it should not format metrics if showRawMetrics is true. And correctly fdisplay and format avg_time_on_site using processed metric value, instead of recalculating in visitor map.

Refs #8060, use bounce_rate metric directly in visitor map instead of calculating using bounce_count (which has to manually requested), and correctly format bounce_rate values in the legend. Bounce rate values must be converted to ints immediately after loading, since API.getProcessedReport will always format percents, and UserCountryMap uses them as if they are integers.

Require UserCountry functions.php file in UserCountryMap so UI tests won't fail (a request from the widgetized dashboard to the UserCountryMap failed because a function in this file was not available).

removed default information from plugin.json files; move plugin descriptions to language files, where available