show "Log out" dialog on logout action
Revert "show "Log out" dialog on logout action"

This reverts commit fbad27ebbe60a6bcab839f10f58b6d2729d76549.
clarify "power" key bindings logic

historically "power" key bindings calls shutdown dialog but described as logout. this is confuses users.
updated "power" key bindings description
provided additional "logout" key bindings
Merge branch 'logout_dialog'