Check_MK Werk 4563: Fix issue with @ in metric title

ID: 4563 Title: Fix issue with @ in metric title Component: metrics Level: 1 Class: Bug fix Version: 1.5.0i1 The @ sign is used to append a custom unit when used within metric titles. This prevents graphs from being displayed when an @ without a special meaning appears within a metric title. The graphing system now checks for an existing unit within the metric title and leaves the title untouched otherwise.