i3bar Bugfix: don't show "EOF" status line error

When the `status_command` sends EOF, it is terminated. Terminating this
process prints an error message to the status line (hence, a race
condition). This error message is always more useful than the former
"EOF" status line error because it shows the exit code.
Merge branch 'fix-eof-msg'
Bugfix: `move <direction>` sends workspace focus

Make sure the command `move <direction>` properly sends the workspace
focus ipc event required for i3bar to be properly updated and redrawn.

Make `ipc_send_workspace_focus_event publicly available from ipc.h for
more flexible event sending.
Merge branch 'fix-move-focus'
add release notes for 4.7.1, update manpage version
Merge branch 'release-4.7.1'