Add sidebar expand and collapse icons - #569

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@colebemis is collapse and expand the correct descriptor for this? not open/close?

@ashygee I'm fine with either.

expand/collapse feel like they represent the action of "expanding" or "collapsing" which is how the icons will be used. open/close feel more like they could be states of the sidebar.

expand/collapse feel like they represent the action of "expanding" or "collapsing" which is how the icons will be used. open/close feel more like they could be states of the sidebar.

This makes perfect sense. let's keep as is then! 🚀 it!