We now replace native scrollbar by custom ones on the list card (which
is required by the new ergonomics in the parent commit), but the
"scrolling engine", is still native, we just hide the scrollbar and
draw our own in HTML/CSS using the perfect-scrollbar package (from
bower).
This commit also implements component scrolling when certain actions
are performed, eg scroll to the bottom when the new card composer is
opened.
The idea is that by displaying card details in a sidebar stuck on the
right of the screen, the mouse had to travel too much before
interacting with it. I also don’t want to use the Trello solution
(modal) on big screens, because I like the ability to interact with
the selected card and with the board at the same time (like in a
e-mail client).
The solution introduced in this commit consist of opening the card
detail in a column next to the minicard list.
This commit also fix right sidebar members and labels drag and drop.
