Improvements and fixes

Metric figures can now be pulled for whole portfolios instead of one plant at a time.

• In the export's metrics view, whole portfolios can now be picked, and every accessible plant inside them is included.
• Weekly, monthly, quarterly and yearly resolutions are offered wherever the chosen period allows them.
• Hovering a chart in the export now shows the metric's name instead of a code.
• The year list in the export no longer offers years after the current one.