Move all the overview templates

Move all the overview-specific templates from the overview
panel into the dashboard-wide templates directory, so that
I can use them in a plugin even if I disabled the original
overview panel.

This is needed for the tuskar_boxes plugin.

Change-Id: Ieabfb6f3334bf8f62a2e35114615b91bb91f3da8
Merge "Move all the overview templates"