Fixes #6664, when replaying logs in log importer, use extra information present in Piwik URLs to determine visitor ID when distributing hits among recorders. If IP is not good enough indicator of visitor, this will increase accuracy of replayed logs.

 Return HTTP 204 instead of GIF for JavaScript tracking.

Refactor out HtmlMessageException 

[automatic translation update] Updated 179 strings in 7 languages (fr, nl, cs, el, da, de, it)

fixes #6663 New command `./console core:plugin list` will list the enabled plugins, one per line, making it easy to compare the list of plugins used in two piwik installs

 Do not store Accept-language full string, only store one detected language

added a new url parameter send_image=0 to disable sending an
image and instead response with a 204 code

Revert "3581 IPv6 support"

Add example archiver and CoreConsole task to generate Archiver into plugin.

Refs #6101, fix sumRowArray error caused by Provider change (GroupBy must be called as ->filter not ->queueFilter since it changes DataTable structure).

Easier configuration to run tests