Add Ability to Send Profile Events (counters) with Cumulative Values to Graphite

Why it matters

This feature enables users to send cumulative values of profile events, such as counters, to Graphite for monitoring and analysis. It helps in tracking metrics over time more effectively by providing cumulative data, improving observability and performance diagnostics.

How to use it

Enable the feature by adding the <events_cumulative> section in the server's config.xml file. This will configure ClickHouse to send profile event counters with cumulative values to Graphite.