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/hint.h

@@ -0,0 +1,66 @@
+#ifndef _HINT_H
+#define _HINT_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.
+ */
+
+/**
+ * @file hint.h The generic hint data that may be attached to buffers
+ *
+ * @verbatim
+ * Revision History
+ *
+ * Date         Who             Description
+ * 10/07/14     Mark Riddoch    Initial implementation
+ *
+ * @endverbatim
+ */
+
+#include <maxscale/skygw_debug.h>
+
+
+/**
+ * The types of hint that are supported by the generic hinting mechanism.
+ */
+typedef enum
+{
+    HINT_ROUTE_TO_MASTER = 1,
+    HINT_ROUTE_TO_SLAVE,
+    HINT_ROUTE_TO_NAMED_SERVER,
+    HINT_ROUTE_TO_UPTODATE_SERVER,
+    HINT_ROUTE_TO_ALL, /*< not implemented yet */
+    HINT_PARAMETER
+} HINT_TYPE;
+
+/**
+ * A generic hint.
+ *
+ * A hint has a type associated with it and may optionally have hint
+ * specific data.
+ * Multiple hints may be attached to a single buffer.
+ */
+typedef struct hint
+{
+    HINT_TYPE       type;   /*< The Type of hint */
+    void            *data;  /*< Type specific data */
+    void            *value; /*< Parameter value for hint */
+    unsigned int    dsize;  /*< Size of the hint data */
+    struct hint     *next;  /*< Another hint for this buffer */
+} HINT;
+
+extern  HINT    *hint_alloc(HINT_TYPE, void *, unsigned int);
+extern  HINT    *hint_create_parameter(HINT *, char *, char *);
+extern  HINT    *hint_create_route(HINT *, HINT_TYPE, char *);
+extern  void    hint_free(HINT *);
+extern  HINT    *hint_dup(HINT *);
+bool            hint_exists(HINT **, HINT_TYPE);
+#endif