sidebar banch: 'all dashboards' selected

[glynhudson]

• When testing sidebar branch when any dashboard is selected "All dashbaoards" are also selected:

• The title of the dashboard menu should be renamed from "Dashboard" > "Dashboards"

• The "main" dashboard (default) should be selected when the user clicks on the dashboard icon

Thanks to @bornpin for these suggestions:

https://community.openenergymonitor.org/t/beta-new-emoncms-sidebar-navigation-layout-feedback-request/10435/32?u=glyn.hudson

[emrysr]

all dashboards link now not incorrectly highlighted:

the "main dashboard" has been relabeled to "default".
The default dashboard is hightlighted in the list and appears on all pages as the first bookmark in the sidebar

[emrysr]

fixed now in master branch