Bug#20052694 - FAILED RESTARTS CONTAIN NO VERSION DETAILS.

In versions 5.5 and 5.6 the MySQL version is not logged until
server is started and ready to accept connections. Exiting
server before this point will not have server version information
in the log. But in 5.7 code, we log a server version information
just after we prepare server_version string and logging is initialized.

For 5.5 and 5.6 code also adding this code to print server version
information.

Test results:
================

5.5
-----
Server version will be logged as below on server startup:
141218  8:45:48 [Note] /home/praveen/WorkDir/mysql_local/bug20052694/mysql/sql/mysqld (mysqld 5.5.42-debug-log) starting as process 19697 ...

5.6
----
Server version will be logged as below on server startup:
2014-12-18 09:08:43 0 [Note] /home/praveen/WorkDir/mysql_local/bug20052694/mysql-5.6/sql/mysqld (mysqld 5.6.23-debug-log) starting as process 18474 ...

sql/mysqld.cc

-/* Copyright (c) 2000, 2014, Oracle and/or its affiliates. All rights
+/* Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights
    reserved.
 
    This program is free software; you can redistribute it and/or modify
@@ -3281,6 +3281,9 @@ static int init_common_variables()
     return 1;
   set_server_version();
 
+  sql_print_information("%s (mysqld %s) starting as process %lu ...",
+                        my_progname, server_version, (ulong) getpid());
+
 #ifndef EMBEDDED_LIBRARY
   if (opt_help && !opt_verbose)
     unireg_abort(0);