In edit email reports screen, display 'Report updated' message on successful update, scroll to title on completion of AJAX (not top of entity container) and show first entityCancelon same level as h2.

Refs #4125  adding backtick so it works if there is no prefix (where `option` is a mysql reserved keyword)

 * updating all variables/methods containing Referers
 * RENAMING custom segments definition, and custom scheduled reports definition, so that when they load "Referers" segment/report it still works as expected
 * RENAMING old archived data so that archived blobs are called Referrers
  * Reverting part of 0deb2bbb
  * Update integration tests generating PDF+HTML with images on my dev box (GD 2.1 and PHP 5.5)

refs #4194 the api ignore tag is not needed, we simply ignore all symfony commands in the api generator

Move deadlock info logging to Db.php, fix core updater translation regression, fix core updater css regression, change logger_message level column to string, and delete unneeded logger tables if not empty. Also includes some changes to travis build.

Removed Piwik::log and replace with calls to Log::... functions. Also changed logging level on travis.

PHP 5.3 (http://www.php.net/manual/de/ini.core.php#ini.zend.ze1-compatibility-mode)

automatic translation update