Zabbix

..F....... [DEV-641] fixed naming of dashboard-related files and actions

Controllers:
 - ControllerWidgetHostStatusView.php => CControllerWidgetProblemHostsView.php

Views:
 - monitoring.widget.hoststatus.view.php => monitoring.widget.problemhosts.view.php

Actions and widget types:
 - widget.hoststatus.view => widget.problemhosts.view

Constants:
 - WIDGET_HOST_STATUS => WIDGET_PROBLEM_HOSTS

Widget names:
 - "Host status" => "Problem hosts"