Make both lefthand and righthand menus collapsible and collapsed by default

[carlynvandyke]

I don't think either menu needs to be visible for people landing on the page. The lefthand menu can continue to use the hamburger button (moved as specified by George here) and the righthand search menu can have a different button to open it. This will also help with our issue of the signals table being too wide to fit on the page.

@BrainIsDead at one point you shared a site that had different options for Django styling, menus, etc.- could you share again?

[BrainIsDead]

https://bootstrapmade.com/nice-admin-bootstrap-admin-html-template/

[BrainIsDead]

Done #32