[Observium] Feature Request/Suggestion: Trending

Hi, it would be really helpful for Capacity Planning to include Trending support, as far as I know, RRDTool already has support for it. Maybe adding trending on all graphs is not the best option, because for one graph there are many data sources, and while one can choose what one thinks would be the most obvious candidate another user might need to do the trending using other datasource...

Maybe adding a separate TAB where one can choose what to graph with trending would be the most "universal" solution, or maybe a mix of both, graph the obvious by default and enable and "advanced" tab for trending on demand...

Regards,