The windowdrag right spacer was acting erratic. It's also not necessary,
since we can just use margins to let the banner buttons fill empty space
so they float to the right side of the tab bar. Without it, though, I
had to add more padding for the add tab button so it has more room.
Only create new tab in `CheckAndFixWindow` if no tabs or pinned tabs
exist
Update `resolvers.resolveTabNum` to account for pinned tabs
Remove obsolete and unused `wstore.DeleteTab`
Only show accelerators for first 9 workspaces in workspace app menu to
be consistent with other keybindings
Fix tabbar spacing to remove min size for drag right spacer, account for
workspace switcher button size
Fix updatebanner size calculations
