Separate timeline navigation from navpanel

Addresses #882 enough to deal with bookmarks and chat without filling the nav panel to extraordinary sizes

Adds a new dropdown (timeline menu) into the timeline header

Moves easy to identify timeline routes from nav panel to dropdown in timeline header (friends, bookmarks, dms, public, twkn)

Changes "The Whole Known Network" into "Known Network" to better deal with too long strings in the header

Is animated