[RoomList Filters] Implement the filters horizontal scroll view

[manuroe]

• Create a horizzontal scroll view that only appears if the room list setting/FF is turned on below the search bar
• This should include the following filters: "Rooms" "People" "Unreads" "Low Priority" "Favourites" (check design for the ordering and naming)
• These filters can be selected and unselected and should change their color according to the selection state
• An X button should appear when at least one filter is selected, to unselected them all at once.

[Velin92]

Kamino cloned this issue to vector-im/element-x-android