libyang CHANGE review header includes

The plugins_types.h was supposed only for implementing data type plugins
code, so I've removed it from libyang.h (now it is supposed to be
included explicitly).
diff --git a/src/xpath.c b/src/xpath.c
index acfeaf4..7eb2e43 100644
--- a/src/xpath.c
+++ b/src/xpath.c
@@ -21,7 +21,6 @@
 #include <assert.h>
 #include <ctype.h>
 #include <errno.h>
-#include <limits.h>
 #include <math.h>
 #include <stdint.h>
 #include <stdio.h>
@@ -33,10 +32,10 @@
 #include "context.h"
 #include "dict.h"
 #include "hash_table.h"
+#include "out.h"
 #include "parser_data.h"
 #include "path.h"
 #include "plugins_types.h"
-#include "out.h"
 #include "printer_data.h"
 #include "schema_compile_node.h"
 #include "tree.h"