WL#5030: Split and remove mysql_priv.h

This patch:

- Moves all definitions from the mysql_priv.h file into
  header files for the component where the variable is
  defined
- Creates header files if the component lacks one
- Eliminates all include directives from mysql_priv.h
- Eliminates all circular include cycles
- Rename time.cc to sql_time.cc
- Rename mysql_priv.h to sql_priv.h

sql/parse_file.h

@@ -17,6 +17,14 @@
 #ifndef _PARSE_FILE_H_
 #define _PARSE_FILE_H_
 
+#include "my_global.h"                          // uchar
+#include "sql_string.h"                         // LEX_STRING
+#include "sql_list.h"                           // Sql_alloc
+
+class THD;
+
+typedef struct st_mem_root MEM_ROOT;
+
 #define PARSE_FILE_TIMESTAMPLENGTH 19
 
 enum file_opt_type {