Merge branch 'feature/client-interface' into develop

include/client/kb-category.inc.php

include/client/knowledgebase.inc.php

include/client/open.inc.php

include/client/tickets.inc.php

include/client/view.inc.php

include/staff/api.inc.php

include/staff/apikeys.inc.php

include/staff/banlist.inc.php

include/staff/cannedreplies.inc.php

include/staff/categories.inc.php

include/staff/directory.inc.php

include/staff/emails.inc.php

include/staff/filters.inc.php

include/staff/helptopics.inc.php

include/staff/settings-general.inc.php

include/staff/slaplans.inc.php

include/staff/staffmembers.inc.php

include/staff/syslogs.inc.php

include/staff/templates.inc.php

include/staff/tickets.inc.php