cleanups done as part of adding encryption

- Fixed compiler warnings
- Added include/wait_for_binlog_checkpoint.inc, as suggested by JonasO
- Updated 'build-tags' to work with git (Patch by Serg)

mysql-test/t/mysqlbinlog.test

@@ -551,6 +551,7 @@ DROP TABLE t1;
 DROP DATABASE test1;
 let $master_binlog= query_get_value(SHOW MASTER STATUS, File, 1);
 FLUSH LOGS;
+--source include/wait_for_binlog_checkpoint.inc
 
 let $MYSQLD_DATADIR= `SELECT @@datadir`;
 exec $MYSQL_BINLOG $MYSQLD_DATADIR/$master_binlog | $MYSQL test 2>&1;