Do not show Close in header bar menu

"Header bar menus shouldn't include a close menu item, since this action
is already provided by the header bar. It can also be ambiguous as to
what a close menu item refers to." -- the HIG

https://bugzilla.gnome.org/show_bug.cgi?id=735539
nautilus-list-view: Avoid unreadable names

Currently if the view is resized, the column name is resized as well
given that use ellipsization allowing the column to become unreadable.
To avoid that, use width-chars property to set a desired width, but at
the same time allowing the user to resize without limits the name column
if desired.

https://bugzilla.gnome.org/show_bug.cgi?id=732004
nautilus-general: Prototype port to gaction