Move headers from server/include to include/maxscale

- Headers now to be included as <maxscale/xyz.h>
- First step, no cleanup of headers has been made. Only moving
  from one place to another + necessary modifications.

include/maxscale/housekeeper.h

@@ -0,0 +1,57 @@
+#ifndef _HOUSEKEEPER_H
+#define _HOUSEKEEPER_H
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl.
+ *
+ * Change Date: 2019-07-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+#include <time.h>
+#include <maxscale/dcb.h>
+#include <maxscale/hk_heartbeat.h>
+/**
+ * @file housekeeper.h A mechanism to have task run periodically
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date         Who             Description
+ * 29/08/14     Mark Riddoch    Initial implementation
+ *
+ * @endverbatim
+ */
+
+typedef enum
+{
+    HK_REPEATED = 1,
+    HK_ONESHOT
+} HKTASK_TYPE;
+
+/**
+ * The housekeeper task list
+ */
+typedef struct hktask
+{
+    char *name;               /*< A simple task name */
+    void (*task)(void *data); /*< The task to call */
+    void *data;               /*< Data to pass the task */
+    int frequency;            /*< How often to call the tasks (seconds) */
+    time_t nextdue;           /*< When the task should be next run */
+    HKTASK_TYPE type;         /*< The task type */
+    struct hktask *next;      /*< Next task in the list */
+} HKTASK;
+
+extern void hkinit();
+extern int  hktask_add(const char *name, void (*task)(void *), void *data, int frequency);
+extern int  hktask_oneshot(const char *name, void (*task)(void *), void *data, int when);
+extern int  hktask_remove(const char *name);
+extern void hkshutdown();
+extern void hkshow_tasks(DCB *pdcb);
+
+#endif