Merge pull request #145 from piwik/translationupdates

[automatic translation update] Updated 652 strings in 3 languages (it, ta, vi)
refs #4223 added some translations and added link to install new plugins
added translation for install new link refs #4223
refs #4223 underline a hovered link
refs #4223 display number of matching plugins
refs #4223 better naming
refs #4223 plugin / theme should be a lower letter
Zeitgeist is bundled with core
Merge remote-tracking branch 'origin/master'
use constant
Refs #4200, finished documenting LogAggregator.
Refs #4234 Fix z-index of calendar so it appears on top of segment editor
Merge remote-tracking branch 'origin/master'
Disabling max execution to help tests generate with code coverage report which can take forever
refs #3917 declaring getUrlsForSocial as a subtable report
updated submodule
do not define subtable for this subtable
refs #3917 better dimension
Refs #4200, tweaking ArchiveProcessor docs.
Refs #4200, documented Archiver class.